Consistent mapping from frame to function

[TimeHorse]

Is there a consistent way to map a frame object to a function / method
object?  Methods usually hang off of parameter 1, and functions
usually in the global or local scope.  But lambda functions and
decorators are not so easily mapped.  You can get access to the
executing code object from the frame, but I don't see a consistent way
to map it to the function.  Any suggestion?