Inspect: flexibility of signature, getfullargspec, getcallargs

Would it be possible/sensible to include follow_wrapper_chains and skip_bound_arg arguments to higher level functions of inspect module?

I sometimes need:
* getcallargs, but without bound_arg
* getfullargspec to follow_wrapper_chains
* signature to include bound_arg.


Or from my POV even better would be:

  1. Add bound_arg to signature() and Signature.from_callable
  2. Have 2 more functions: getfullargspec_from_signature, getcallargs_from_fullargspec
  3. Use those 2 functions in getfullargspec and getcallargs.

This way:
a) signatures of existing functions are (almost) not modified
b) Allows user to get what he needs with all parameter combinations

The only tiny ambiguous nuance that I can see is getcallargs implicitly retrieving __self__ if ismethod(func). If fullargspec was run with skip_bound_arg=True, then this step would need to be omitted.