When call socket._fileobject, return error: 'module' object has no attribute '_fileobject'

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Jython 2.2.1 (don't work)
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C:\jython2.2.1>jython.bat
>>> import socket
>>> socket._fileobject
Traceback (innermost last):
File "<console>", line 1, in ?
AttributeError: 'module' object has no attribute '_fileobject'


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Python 2.5 (work fine)
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C:\Python25>python.exe
>>> import socket
>>> socket._fileobject
<class 'socket._fileobject'>


Anyone can help me?


Thanks.