Python debugger: To run pdb, how fix wrong path & filename & scriptname on command line???

[Christian Seberino]

When you try to run the Python debugger in Emacs with pdb command
it asks you what the desired command line to invoke pdb is.

It assumes script is pdb and not pdb.py.  Also, the path is missing
so Emacs says it cannot find pdb.py script.

Also, the filename is not always correct.

How fix the entire command line for all invocations of pdb??

Chris