Python regular expression help

Question

I've got a python string

s = "Abc(problem=None, fds=5, sff=(2, 1, 0))"
s2 = "Abc(problem=None)"

What I want to do is remove the "problem=None, "

So it'll looks like

s = "Abc(fds=5, sff=(2, 1, 0))"
s2 = "Abc()"

Please mind the ','

How to achieve this? Thanks very much!!

Answer 1

A regex that will work in both cases is:

/problem=None,?\s*/

The ? makes the comma optional and the \s* will strip any trailing whitespace.

Answer 2

re.sub(r"problem=None,? +", "", s)

Answer 3

Removing all syntactically valid whitespace:

>>> import re
>>> re.sub(r"\s*problem\s*=\s*None\s*,?\s*", "", "abc( problem = None , )")
'abc()'
>>> re.sub(r"\s*problem\s*=\s*None\s*,?\s*", "", "abc( problem = None  )")
'abc()'
>>>