Click errors out when running on Windows with the GAE development server sandbox

[cdman]

This prevents Flask 0.12 from running under the GAE development server on Windows. See this issue: pallets/flask#2139

Probably the pragmatic solution here is:

• add a try/catch around importing msvcrt: https://github.com/pallets/click/blob/master/click/_compat.py#L166
• if the import fails, log a warning (error?) and just use set_binary_mode = lambda x: x
• or perhaps we can be stricter and say that set_binary_mode won't work in this case and use set_binary_mode = lambda _: None?

[yairohayon]

This fix is no good - still opening with Flask 0.12 and Click 6.7

[sorgloomer]

Created App Engine issue, maybe they can push this better or provide a builtin workaround: https://issuetracker.google.com/issues/72043776