How to guard against nulls in python -

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in python, how check if string either null or empty?

in c# have string.isnullorempty(some_string)

also, i'm doing regex like:

p = re.compile(...)  = p.search(..).group(1)

this break if group doesn't have @ index 1, how guard against ? i.e. how re-write 2 lines safely?

just check it. explicit better implicit, , 1 more line won't kill you.

a = p.search(...) if not none:     # ...

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