OSError: [WinError 10042] when making connection

[arouax]

This issue: #370 is present again on Windows as of version 0.47.0 (incorrect merge perhaps?)
If I manually add the fixes introduced in this commit: 1135431, then everything works OK again.

[ghost]

This is a bug of Python 3.6.4, https://bugs.python.org/issue32394

There are two solutions:

1. Upgrade to Windows 10 1703+, which supports TCP_KEEPCNT flag.
2. Use Python 3.6.3 (always hide TCP_KEEPCNT flag), or Use Python 3.6.5+ (hide TCP_KEEPCNT flag when unusable).

[engn33r]

Closing this issue since it appears to be a bug in Python, not this library. Thanks for the help @animalize!