Tools to work help with inspecting function calls

The functions update_wrapper and wraps improve on functools.update_wrapper and functools.wraps by persisting information about function signatures. The function get_argspec is similar to inspect.get_argspec, except it first tries to use the metadata provided by update_wrapper.

The function get_callargs is similar to inspect.getcallargs, except that

• it can access the metadata created by update_wrapper
• it does not raise when a call is illegal but rather makes a best guess, which makes it suitable for logging and error handling in decorators.