The pdb module stand for Python debugger. It is used on the bdb debugger framework.
And we can run the debugger from the command line and go to the next line and help to get a list of available commands. For example you can see below code.
$pdb.py sum.py
> /test/sum.py(3)()
-> import dis
(Pdb) n
> /test/sum.py(5)()
-> def sum():
(Pdb) n
>/test/sum.py(14)()
-> dis.dis(sum)
(Pdb) n
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