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2to3.html
63.71
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__builtin__.html
11.79
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__future__.html
15.58
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__main__.html
8.33
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_winreg.html
73.99
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abc.html
26.82
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aepack.html
15.47
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aetools.html
18.79
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aetypes.html
27.08
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aifc.html
29.59
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al.html
22.13
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allos.html
35.48
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anydbm.html
19.31
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archiving.html
10.64
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argparse.html
269.59
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array.html
35.35
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ast.html
42.42
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asynchat.html
35.84
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asyncore.html
43.22
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atexit.html
19.23
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audioop.html
41.32
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autogil.html
9.77
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base64.html
24.8
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basehttpserver.html
40.6
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bastion.html
13.02
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bdb.html
50.06
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binascii.html
26.64
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binhex.html
12.66
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bisect.html
28.52
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bsddb.html
32.02
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bz2.html
31.92
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calendar.html
50.16
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carbon.html
54.14
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cd.html
35.24
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cgi.html
58.4
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cgihttpserver.html
15.12
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cgitb.html
13.5
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chunk.html
17.41
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cmath.html
32.41
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cmd.html
32.69
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code.html
28.92
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codecs.html
125.92
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codeop.html
16.42
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collections.html
150.36
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colorpicker.html
9.02
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colorsys.html
14.38
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commands.html
16.63
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compileall.html
21.18
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compiler.html
78.14
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configparser.html
73.92
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constants.html
14.68
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contextlib.html
22.91
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cookie.html
45.38
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cookielib.html
102.78
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copy.html
14.21
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copy_reg.html
15.82
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crypt.html
11.62
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crypto.html
8.35
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csv.html
82.79
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ctypes.html
280.57
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curses.ascii.html
28.97
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curses.html
200.94
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curses.panel.html
18.43
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custominterp.html
8.59
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datatypes.html
18.84
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datetime.html
261.02
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dbhash.html
18.4
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dbm.html
14.75
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debug.html
11.28
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decimal.html
239.14
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development.html
15.27
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difflib.html
96.93
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dircache.html
13.66
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dis.html
96.52
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distribution.html
8.27
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distutils.html
10.97
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dl.html
19.27
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doctest.html
193.18
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docxmlrpcserver.html
20.02
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dumbdbm.html
16.74
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dummy_thread.html
11.04
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dummy_threading.html
9.96
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easydialogs.html
38.83
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email-examples.html
47.2
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email.charset.html
32.45
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email.encoders.html
14.09
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email.errors.html
19.2
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email.generator.html
24.78
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email.header.html
31.12
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email.html
55.3
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email.iterators.html
14.22
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email.message.html
74.91
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email.mime.html
34.51
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email.parser.html
37.09
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email.utils.html
30.04
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ensurepip.html
20.21
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errno.html
52.31
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exceptions.html
73.4
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fcntl.html
27.85
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filecmp.html
26.49
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fileformats.html
10.21
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fileinput.html
29.36
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filesys.html
11.55
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fl.html
71.58
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fm.html
15
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fnmatch.html
17.78
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formatter.html
43.91
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fpectl.html
17.84
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fpformat.html
12.65
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fractions.html
27.17
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framework.html
44.24
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frameworks.html
8.11
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ftplib.html
56.56
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functions.html
216.84
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functools.html
31.06
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future_builtins.html
15.9
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gc.html
30.74
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gdbm.html
19.35
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gensuitemodule.html
14.54
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getopt.html
26.56
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getpass.html
12.5
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gettext.html
91.32
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gl.html
26.71
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glob.html
15.42
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grp.html
12.33
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gzip.html
21.95
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hashlib.html
27.4
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heapq.html
36.72
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hmac.html
15.97
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hotshot.html
22.69
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htmllib.html
29.9
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htmlparser.html
45.11
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httplib.html
78.55
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i18n.html
10.61
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ic.html
22.03
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idle.html
45.74
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imageop.html
20.94
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imaplib.html
69.9
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imgfile.html
14.91
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imghdr.html
13.43
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imp.html
41.48
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importlib.html
10.27
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imputil.html
36.11
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index.html
82.54
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inspect.html
64.31
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internet.html
26.77
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intro.html
9.76
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io.html
122.3
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ipc.html
17.18
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itertools.html
129.91
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jpeg.html
15.36
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json.html
79.09
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keyword.html
9.27
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language.html
12.35
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linecache.html
12.7
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locale.html
68.54
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logging.config.html
82.23
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logging.handlers.html
91.96
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logging.html
123.15
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mac.html
24.49
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macos.html
18.51
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macosa.html
14.55
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macostools.html
19.67
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macpath.html
9.19
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mailbox.html
185.53
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mailcap.html
15.3
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markup.html
20.37
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marshal.html
19.88
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math.html
50.52
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md5.html
16.65
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mhlib.html
30.04
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mimetools.html
23.84
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mimetypes.html
35.82
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mimewriter.html
18.19
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mimify.html
16.96
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miniaeframe.html
14.5
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misc.html
7.77
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mm.html
10.19
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mmap.html
33.52
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modulefinder.html
19.85
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modules.html
9.68
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msilib.html
72.78
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msvcrt.html
24.1
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multifile.html
28.82
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multiprocessing.html
423.97
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mutex.html
13.56
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netdata.html
19.28
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netrc.html
15.51
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new.html
16.1
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nis.html
13.19
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nntplib.html
51.08
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numbers.html
40.91
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numeric.html
14.85
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operator.html
118.32
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optparse.html
251.08
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os.html
270.49
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os.path.html
48.87
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ossaudiodev.html
49.79
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othergui.html
9.98
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parser.html
44.52
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pdb.html
41.44
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persistence.html
16.25
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pickle.html
107.94
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pickletools.html
13.21
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pipes.html
21.85
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pkgutil.html
30.59
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platform.html
40.14
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plistlib.html
20.96
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popen2.html
30.13
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poplib.html
27.93
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posix.html
17.27
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posixfile.html
23.68
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pprint.html
36.42
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profile.html
76.65
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pty.html
11.42
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pwd.html
13.53
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py_compile.html
13.33
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pyclbr.html
18.14
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pydoc.html
14.33
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pyexpat.html
93.28
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python.html
13.53
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queue.html
29.64
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quopri.html
14.5
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random.html
47.78
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re.html
163.11
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readline.html
41.2
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repr.html
24.57
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resource.html
30.86
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restricted.html
12.69
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rexec.html
43.59
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rfc822.html
51.25
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rlcompleter.html
15.29
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robotparser.html
15.01
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runpy.html
23.55
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sched.html
21.76
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scrolledtext.html
10.67
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select.html
50.17
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sets.html
39.92
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sgi.html
11.09
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sgmllib.html
38.77
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sha.html
14.55
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shelve.html
32.93
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shlex.html
38.43
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shutil.html
49.49
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signal.html
36.52
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simplehttpserver.html
21.57
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simplexmlrpcserver.html
40.41
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site.html
29
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smtpd.html
15.64
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smtplib.html
51.86
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sndhdr.html
12.05
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socket.html
126.94
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socketserver.html
81.38
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someos.html
17.09
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spwd.html
12.25
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sqlite3.html
154.12
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ssl.html
214.5
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stat.html
41.11
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statvfs.html
13.24
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stdtypes.html
309.83
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string.html
129.58
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stringio.html
21.1
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stringprep.html
21.4
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strings.html
16.42
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struct.html
47.68
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subprocess.html
117
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sun.html
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sunau.html
35.43
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sunaudio.html
21.05
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symbol.html
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symtable.html
29.03
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sys.html
118.12
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sysconfig.html
28.8
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syslog.html
21.29
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tabnanny.html
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tarfile.html
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telnetlib.html
30.46
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tempfile.html
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termios.html
19.22
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test.html
61.42
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textwrap.html
32.28
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thread.html
22.67
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threading.html
92.04
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time.html
65.55
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timeit.html
44.38
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tix.html
56.73
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tk.html
26.76
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tkinter.html
86.67
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token.html
27.31
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tokenize.html
21.69
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trace.html
33.91
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traceback.html
44.22
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ttk.html
123.83
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tty.html
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turtle.html
246.17
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types.html
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undoc.html
25.54
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unicodedata.html
22.64
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unittest.html
246.75
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unix.html
11.9
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urllib.html
71.61
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urllib2.html
128.77
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urlparse.html
49.04
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user.html
13.41
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userdict.html
32.96
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uu.html
13.25
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uuid.html
33.55
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warnings.html
51.86
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wave.html
29.08
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weakref.html
41.14
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webbrowser.html
29.53
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whichdb.html
10.44
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windows.html
10.37
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winsound.html
22.56
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wsgiref.html
94.38
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xdrlib.html
38.05
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xml.dom.html
110.39
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xml.dom.minidom.html
45.23
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xml.dom.pulldom.html
16.32
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xml.etree.elementtree.html
124.2
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xml.html
18.76
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xml.sax.handler.html
47.5
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xml.sax.html
26.04
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xml.sax.reader.html
51.4
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xml.sax.utils.html
18.11
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xmlrpclib.html
71.79
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zipfile.html
67.26
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zipimport.html
24.32
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zlib.html
34.41
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<!DOCTYPE html> <html> <head> <meta charset="utf-8" /> <meta name="viewport" content="width=device-width, initial-scale=1.0" /><meta name="generator" content="Docutils 0.17.1: http://docutils.sourceforge.net/" /> <title>28.7. contextlib — Utilities for with-statement contexts — Python 2.7.18 documentation</title> <link rel="stylesheet" type="text/css" href="../_static/pygments.css" /> <link rel="stylesheet" type="text/css" href="../_static/classic.css" /> <script data-url_root="../" id="documentation_options" src="../_static/documentation_options.js"></script> <script src="../_static/jquery.js"></script> <script src="../_static/underscore.js"></script> <script src="../_static/doctools.js"></script> <script src="../_static/sidebar.js"></script> <link rel="search" type="application/opensearchdescription+xml" title="Search within Python 2.7.18 documentation" href="../_static/opensearch.xml"/> <link rel="author" title="About these documents" href="../about.html" /> <link rel="index" title="Index" href="../genindex.html" /> <link rel="search" title="Search" href="../search.html" /> <link rel="copyright" title="Copyright" href="../copyright.html" /> <link rel="next" title="28.8. abc — Abstract Base Classes" href="abc.html" /> <link rel="prev" title="28.6. warnings — Warning control" href="warnings.html" /> <link rel="shortcut icon" type="image/png" href="../_static/py.png" /> <link rel="canonical" href="file:///usr/share/doc/python2.7/html/library/contextlib.html" /> <script type="text/javascript" src="../_static/copybutton.js"></script> </head><body> <div id="outdated-warning" style="padding: .5em; text-align: center; background-color: #FFBABA; color: #6A0E0E;"> This document is for an old version of Python that is <a href="https://devguide.python.org/devcycle/#end-of-life-branches">no longer supported</a>. You should install the python3 and python3-doc packages and read the <a href="file:///usr/share/doc/python3-doc/html/library/contextlib.html"> Python documentation for the Python3 version packaged in this release</a>. </div> <div class="related" role="navigation" aria-label="related navigation"> <h3>Navigation</h3> <ul> <li class="right" style="margin-right: 10px"> <a href="../genindex.html" title="General Index" accesskey="I">index</a></li> <li class="right" > <a href="../py-modindex.html" title="Python Module Index" >modules</a> |</li> <li class="right" > <a href="abc.html" title="28.8. abc — Abstract Base Classes" accesskey="N">next</a> |</li> <li class="right" > <a href="warnings.html" title="28.6. warnings — Warning control" accesskey="P">previous</a> |</li> <li><img src="../_static/py.png" alt="" style="vertical-align: middle; margin-top: -1px"/></li> <li><a href="https://www.python.org/">Python</a> »</li> <li> <a href="../index.html">Python 2.7.18 documentation</a> » </li> <li class="nav-item nav-item-1"><a href="index.html" >The Python Standard Library</a> »</li> <li class="nav-item nav-item-2"><a href="python.html" accesskey="U"><span class="section-number">28. </span>Python Runtime Services</a> »</li> <li class="nav-item nav-item-this"><a href=""><span class="section-number">28.7. </span><code class="xref py py-mod docutils literal notranslate"><span class="pre">contextlib</span></code> — Utilities for <code class="xref std std-keyword docutils literal notranslate"><span class="pre">with</span></code>-statement contexts</a></li> </ul> </div> <div class="document"> <div class="documentwrapper"> <div class="bodywrapper"> <div class="body" role="main"> <section id="module-contextlib"> <span id="contextlib-utilities-for-with-statement-contexts"></span><h1><span class="section-number">28.7. </span><a class="reference internal" href="#module-contextlib" title="contextlib: Utilities for with-statement contexts."><code class="xref py py-mod docutils literal notranslate"><span class="pre">contextlib</span></code></a> — Utilities for <a class="reference internal" href="../reference/compound_stmts.html#with"><code class="xref std std-keyword docutils literal notranslate"><span class="pre">with</span></code></a>-statement contexts<a class="headerlink" href="#module-contextlib" title="Permalink to this headline">¶</a></h1> <div class="versionadded"> <p><span class="versionmodified added">New in version 2.5.</span></p> </div> <p><strong>Source code:</strong> <a class="reference external" href="https://github.com/python/cpython/tree/2.7/Lib/contextlib.py">Lib/contextlib.py</a></p> <hr class="docutils" /> <p>This module provides utilities for common tasks involving the <a class="reference internal" href="../reference/compound_stmts.html#with"><code class="xref std std-keyword docutils literal notranslate"><span class="pre">with</span></code></a> statement. For more information see also <a class="reference internal" href="stdtypes.html#typecontextmanager"><span class="std std-ref">Context Manager Types</span></a> and <a class="reference internal" href="../reference/datamodel.html#context-managers"><span class="std std-ref">With Statement Context Managers</span></a>.</p> <p>Functions provided:</p> <dl class="py function"> <dt class="sig sig-object py" id="contextlib.contextmanager"> <span class="sig-prename descclassname"><span class="pre">contextlib.</span></span><span class="sig-name descname"><span class="pre">contextmanager</span></span><span class="sig-paren">(</span><em class="sig-param"><span class="n"><span class="pre">func</span></span></em><span class="sig-paren">)</span><a class="headerlink" href="#contextlib.contextmanager" title="Permalink to this definition">¶</a></dt> <dd><p>This function is a <a class="reference internal" href="../glossary.html#term-decorator"><span class="xref std std-term">decorator</span></a> that can be used to define a factory function for <a class="reference internal" href="../reference/compound_stmts.html#with"><code class="xref std std-keyword docutils literal notranslate"><span class="pre">with</span></code></a> statement context managers, without needing to create a class or separate <code class="xref py py-meth docutils literal notranslate"><span class="pre">__enter__()</span></code> and <code class="xref py py-meth docutils literal notranslate"><span class="pre">__exit__()</span></code> methods.</p> <p>While many objects natively support use in with statements, sometimes a resource needs to be managed that isn’t a context manager in its own right, and doesn’t implement a <code class="docutils literal notranslate"><span class="pre">close()</span></code> method for use with <code class="docutils literal notranslate"><span class="pre">contextlib.closing</span></code></p> <p>An abstract example would be the following to ensure correct resource management:</p> <div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="kn">from</span> <span class="nn">contextlib</span> <span class="kn">import</span> <span class="n">contextmanager</span> <span class="nd">@contextmanager</span> <span class="k">def</span> <span class="nf">managed_resource</span><span class="p">(</span><span class="o">*</span><span class="n">args</span><span class="p">,</span> <span class="o">**</span><span class="n">kwds</span><span class="p">):</span> <span class="c1"># Code to acquire resource, e.g.:</span> <span class="n">resource</span> <span class="o">=</span> <span class="n">acquire_resource</span><span class="p">(</span><span class="o">*</span><span class="n">args</span><span class="p">,</span> <span class="o">**</span><span class="n">kwds</span><span class="p">)</span> <span class="k">try</span><span class="p">:</span> <span class="k">yield</span> <span class="n">resource</span> <span class="k">finally</span><span class="p">:</span> <span class="c1"># Code to release resource, e.g.:</span> <span class="n">release_resource</span><span class="p">(</span><span class="n">resource</span><span class="p">)</span> <span class="o">>>></span> <span class="k">with</span> <span class="n">managed_resource</span><span class="p">(</span><span class="n">timeout</span><span class="o">=</span><span class="mi">3600</span><span class="p">)</span> <span class="k">as</span> <span class="n">resource</span><span class="p">:</span> <span class="o">...</span> <span class="c1"># Resource is released at the end of this block,</span> <span class="o">...</span> <span class="c1"># even if code in the block raises an exception</span> </pre></div> </div> <p>The function being decorated must return a <a class="reference internal" href="../glossary.html#term-generator"><span class="xref std std-term">generator</span></a>-iterator when called. This iterator must yield exactly one value, which will be bound to the targets in the <a class="reference internal" href="../reference/compound_stmts.html#with"><code class="xref std std-keyword docutils literal notranslate"><span class="pre">with</span></code></a> statement’s <a class="reference internal" href="../reference/compound_stmts.html#as"><code class="xref std std-keyword docutils literal notranslate"><span class="pre">as</span></code></a> clause, if any.</p> <p>At the point where the generator yields, the block nested in the <a class="reference internal" href="../reference/compound_stmts.html#with"><code class="xref std std-keyword docutils literal notranslate"><span class="pre">with</span></code></a> statement is executed. The generator is then resumed after the block is exited. If an unhandled exception occurs in the block, it is reraised inside the generator at the point where the yield occurred. Thus, you can use a <a class="reference internal" href="../reference/compound_stmts.html#try"><code class="xref std std-keyword docutils literal notranslate"><span class="pre">try</span></code></a>…<a class="reference internal" href="../reference/compound_stmts.html#except"><code class="xref std std-keyword docutils literal notranslate"><span class="pre">except</span></code></a>…<a class="reference internal" href="../reference/compound_stmts.html#finally"><code class="xref std std-keyword docutils literal notranslate"><span class="pre">finally</span></code></a> statement to trap the error (if any), or ensure that some cleanup takes place. If an exception is trapped merely in order to log it or to perform some action (rather than to suppress it entirely), the generator must reraise that exception. Otherwise the generator context manager will indicate to the <a class="reference internal" href="../reference/compound_stmts.html#with"><code class="xref std std-keyword docutils literal notranslate"><span class="pre">with</span></code></a> statement that the exception has been handled, and execution will resume with the statement immediately following the <a class="reference internal" href="../reference/compound_stmts.html#with"><code class="xref std std-keyword docutils literal notranslate"><span class="pre">with</span></code></a> statement.</p> </dd></dl> <dl class="py function"> <dt class="sig sig-object py" id="contextlib.nested"> <span class="sig-prename descclassname"><span class="pre">contextlib.</span></span><span class="sig-name descname"><span class="pre">nested</span></span><span class="sig-paren">(</span><em class="sig-param"><span class="n"><span class="pre">mgr1</span></span></em><span class="optional">[</span>, <em class="sig-param"><span class="n"><span class="pre">mgr2</span></span></em><span class="optional">[</span>, <em class="sig-param"><span class="n"><span class="pre">...</span></span></em><span class="optional">]</span><span class="optional">]</span><span class="sig-paren">)</span><a class="headerlink" href="#contextlib.nested" title="Permalink to this definition">¶</a></dt> <dd><p>Combine multiple context managers into a single nested context manager.</p> <p>This function has been deprecated in favour of the multiple manager form of the <a class="reference internal" href="../reference/compound_stmts.html#with"><code class="xref std std-keyword docutils literal notranslate"><span class="pre">with</span></code></a> statement.</p> <p>The one advantage of this function over the multiple manager form of the <a class="reference internal" href="../reference/compound_stmts.html#with"><code class="xref std std-keyword docutils literal notranslate"><span class="pre">with</span></code></a> statement is that argument unpacking allows it to be used with a variable number of context managers as follows:</p> <div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="kn">from</span> <span class="nn">contextlib</span> <span class="kn">import</span> <span class="n">nested</span> <span class="k">with</span> <span class="n">nested</span><span class="p">(</span><span class="o">*</span><span class="n">managers</span><span class="p">):</span> <span class="n">do_something</span><span class="p">()</span> </pre></div> </div> <p>Note that if the <code class="xref py py-meth docutils literal notranslate"><span class="pre">__exit__()</span></code> method of one of the nested context managers indicates an exception should be suppressed, no exception information will be passed to any remaining outer context managers. Similarly, if the <code class="xref py py-meth docutils literal notranslate"><span class="pre">__exit__()</span></code> method of one of the nested managers raises an exception, any previous exception state will be lost; the new exception will be passed to the <code class="xref py py-meth docutils literal notranslate"><span class="pre">__exit__()</span></code> methods of any remaining outer context managers. In general, <code class="xref py py-meth docutils literal notranslate"><span class="pre">__exit__()</span></code> methods should avoid raising exceptions, and in particular they should not re-raise a passed-in exception.</p> <p>This function has two major quirks that have led to it being deprecated. Firstly, as the context managers are all constructed before the function is invoked, the <code class="xref py py-meth docutils literal notranslate"><span class="pre">__new__()</span></code> and <code class="xref py py-meth docutils literal notranslate"><span class="pre">__init__()</span></code> methods of the inner context managers are not actually covered by the scope of the outer context managers. That means, for example, that using <a class="reference internal" href="#contextlib.nested" title="contextlib.nested"><code class="xref py py-func docutils literal notranslate"><span class="pre">nested()</span></code></a> to open two files is a programming error as the first file will not be closed promptly if an exception is thrown when opening the second file.</p> <p>Secondly, if the <code class="xref py py-meth docutils literal notranslate"><span class="pre">__enter__()</span></code> method of one of the inner context managers raises an exception that is caught and suppressed by the <code class="xref py py-meth docutils literal notranslate"><span class="pre">__exit__()</span></code> method of one of the outer context managers, this construct will raise <code class="xref py py-exc docutils literal notranslate"><span class="pre">RuntimeError</span></code> rather than skipping the body of the <a class="reference internal" href="../reference/compound_stmts.html#with"><code class="xref std std-keyword docutils literal notranslate"><span class="pre">with</span></code></a> statement.</p> <p>Developers that need to support nesting of a variable number of context managers can either use the <a class="reference internal" href="warnings.html#module-warnings" title="warnings: Issue warning messages and control their disposition."><code class="xref py py-mod docutils literal notranslate"><span class="pre">warnings</span></code></a> module to suppress the DeprecationWarning raised by this function or else use this function as a model for an application specific implementation.</p> <div class="deprecated"> <p><span class="versionmodified deprecated">Deprecated since version 2.7: </span>The with-statement now supports this functionality directly (without the confusing error prone quirks).</p> </div> </dd></dl> <dl class="py function"> <dt class="sig sig-object py" id="contextlib.closing"> <span class="sig-prename descclassname"><span class="pre">contextlib.</span></span><span class="sig-name descname"><span class="pre">closing</span></span><span class="sig-paren">(</span><em class="sig-param"><span class="n"><span class="pre">thing</span></span></em><span class="sig-paren">)</span><a class="headerlink" href="#contextlib.closing" title="Permalink to this definition">¶</a></dt> <dd><p>Return a context manager that closes <em>thing</em> upon completion of the block. This is basically equivalent to:</p> <div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="kn">from</span> <span class="nn">contextlib</span> <span class="kn">import</span> <span class="n">contextmanager</span> <span class="nd">@contextmanager</span> <span class="k">def</span> <span class="nf">closing</span><span class="p">(</span><span class="n">thing</span><span class="p">):</span> <span class="k">try</span><span class="p">:</span> <span class="k">yield</span> <span class="n">thing</span> <span class="k">finally</span><span class="p">:</span> <span class="n">thing</span><span class="o">.</span><span class="n">close</span><span class="p">()</span> </pre></div> </div> <p>And lets you write code like this:</p> <div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="kn">from</span> <span class="nn">contextlib</span> <span class="kn">import</span> <span class="n">closing</span> <span class="kn">import</span> <span class="nn">urllib</span> <span class="k">with</span> <span class="n">closing</span><span class="p">(</span><span class="n">urllib</span><span class="o">.</span><span class="n">urlopen</span><span class="p">(</span><span class="s1">'http://www.python.org'</span><span class="p">))</span> <span class="k">as</span> <span class="n">page</span><span class="p">:</span> <span class="k">for</span> <span class="n">line</span> <span class="ow">in</span> <span class="n">page</span><span class="p">:</span> <span class="nb">print</span> <span class="n">line</span> </pre></div> </div> <p>without needing to explicitly close <code class="docutils literal notranslate"><span class="pre">page</span></code>. Even if an error occurs, <code class="docutils literal notranslate"><span class="pre">page.close()</span></code> will be called when the <a class="reference internal" href="../reference/compound_stmts.html#with"><code class="xref std std-keyword docutils literal notranslate"><span class="pre">with</span></code></a> block is exited.</p> </dd></dl> <div class="admonition seealso"> <p class="admonition-title">See also</p> <dl class="simple"> <dt><span class="target" id="index-0"></span><a class="pep reference external" href="https://www.python.org/dev/peps/pep-0343"><strong>PEP 343</strong></a> - The “with” statement</dt><dd><p>The specification, background, and examples for the Python <a class="reference internal" href="../reference/compound_stmts.html#with"><code class="xref std std-keyword docutils literal notranslate"><span class="pre">with</span></code></a> statement.</p> </dd> </dl> </div> </section> <div class="clearer"></div> </div> </div> </div> <div class="sphinxsidebar" role="navigation" aria-label="main navigation"> <div class="sphinxsidebarwrapper"> <h4>Previous topic</h4> <p class="topless"><a href="warnings.html" title="previous chapter"><span class="section-number">28.6. </span><code class="xref py py-mod docutils literal notranslate"><span class="pre">warnings</span></code> — Warning control</a></p> <h4>Next topic</h4> <p class="topless"><a href="abc.html" title="next chapter"><span class="section-number">28.8. </span><code class="xref py py-mod docutils literal notranslate"><span class="pre">abc</span></code> — Abstract Base Classes</a></p> <div role="note" aria-label="source link"> <h3>This Page</h3> <ul class="this-page-menu"> <li><a href="../_sources/library/contextlib.rst.txt" rel="nofollow">Show Source</a></li> </ul> </div> <div id="searchbox" style="display: none" role="search"> <h3 id="searchlabel">Quick search</h3> <div class="searchformwrapper"> <form class="search" action="../search.html" method="get"> <input type="text" name="q" aria-labelledby="searchlabel" autocomplete="off" autocorrect="off" autocapitalize="off" spellcheck="false"/> <input type="submit" value="Go" /> </form> </div> </div> <script>$('#searchbox').show(0);</script> </div> </div> <div class="clearer"></div> </div> <div class="related" role="navigation" aria-label="related navigation"> <h3>Navigation</h3> <ul> <li class="right" style="margin-right: 10px"> <a href="../genindex.html" title="General Index" >index</a></li> <li class="right" > <a href="../py-modindex.html" title="Python Module Index" >modules</a> |</li> <li class="right" > <a href="abc.html" title="28.8. abc — Abstract Base Classes" >next</a> |</li> <li class="right" > <a href="warnings.html" title="28.6. warnings — Warning control" >previous</a> |</li> <li><img src="../_static/py.png" alt="" style="vertical-align: middle; margin-top: -1px"/></li> <li><a href="https://www.python.org/">Python</a> »</li> <li> <a href="../index.html">Python 2.7.18 documentation</a> » </li> <li class="nav-item nav-item-1"><a href="index.html" >The Python Standard Library</a> »</li> <li class="nav-item nav-item-2"><a href="python.html" ><span class="section-number">28. </span>Python Runtime Services</a> »</li> <li class="nav-item nav-item-this"><a href=""><span class="section-number">28.7. </span><code class="xref py py-mod docutils literal notranslate"><span class="pre">contextlib</span></code> — Utilities for <code class="xref std std-keyword docutils literal notranslate"><span class="pre">with</span></code>-statement contexts</a></li> </ul> </div> <div class="footer"> © <a href="../copyright.html">Copyright</a> 1990-2024, Python Software Foundation. <br /> The Python Software Foundation is a non-profit corporation. <a href="https://www.python.org/psf/donations/">Please donate.</a> <br /> Last updated on December 09, 2024. <a href="../bugs.html">Found a bug</a>? <br /> Created using <a href="http://sphinx.pocoo.org/">Sphinx</a> 4.3.2. </div> </body> </html>
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