Hello. I failed to build py3k on cygwin (configure --without-threads).
It's because io.py imports _dummy_thread, and it imports traceback, and
it tries to import c-module itertools which is not built yet.

Attached file is workaround patch.

/////////////////////////////

Fatal Python error: Py_Initialize: can't initialize sys standard streams
Traceback (most recent call last):
  File "/home/WhiteRabbit/python-dev/py3k/Lib/io.py", line 64, in <module>
    from _thread import allocate_lock as Lock
ImportError: No module named _thread

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/home/WhiteRabbit/python-dev/py3k/Lib/io.py", line 66, in <module>
    from _dummy_thread import allocate_lock as Lock
  File "/home/WhiteRabbit/python-dev/py3k/Lib/_dummy_thread.py", line
19, in <mo
dule>
    import traceback as _traceback
  File "/home/WhiteRabbit/python-dev/py3k/Lib/traceback.py", line 6, in
<module>

    import itertools
ImportError: No module named itertools
Aborted (core dumped)