bug#25194: 25.1; Python debugger breakpoint error

[Live System User]

Hi,

        When trying to debug a Python program, I get the following
        error when trying to set a breakpoint:

0. emaccs -Q &

1. C-x C-f test.py

2. From the menubar:  Python->Debugger

Run pdb (like this): python -m pdb test.py

3. Click on "Next Line" so I can see a source line

4. Cick on "Set Breakpoint"

   I now get the error:
   
      Wrong type argument: stringp, nil

   Turning on `debug-on-error' yields the same results.
   However, on the *Messages* buffer there is a little more
   information about the error:

       gud-format-command: Wrong type argument: stringp, nil

   How does one debug this problem further?

   Thanks.
   



In GNU Emacs 25.1.1 (x86_64-redhat-linux-gnu, GTK+ Version 3.20.9)
 of 2016-10-13 built on buildvm-05.phx2.fedoraproject.org
Windowing system distributor 'Fedora Project', version 11.0.11803000
Configured using:
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 --host=x86_64-redhat-linux-gnu --program-prefix=
 --disable-dependency-tracking --prefix=/usr --exec-prefix=/usr
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Memory information:
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