bpo-19903: IDLE: Change to inspect.signature for calltips by louisom · Pull Request #1382 · python/cpython

This commit change the get_argspec from using inspect.getfullargspec
to inspect.signature. It will improve the tip message for use.

Also, if object is not callable, now will return this message for
user, not blank tips. If the methods has an invalid method signature,
it will also return message to user.