Python `in` keyword gives false positivies

Question

I've been using in keyword to check if a character is available in a tuple and ran into a weird result. I'd appreciate if someone could explain the last result below. Thank you in advance.

>>> '' in ('n','p','')
True
>>> '' in ('n','p')
False
>>> '' in ('n')
True

Edit

As explained in Anthony's comment, it seems I've mistaken ('n') - which is just a string in parenthesis - as a tuple. Using ('n',) worked as expected.

`('n')` is not a tuple, that's a parenthesized string. you want `('n',)` — anthony sottile, Sep 05 '21 at 13:26
@ParaD you might be interested with this thread :) https://stackoverflow.com/questions/40192449/why-are-str-count-and-lenstr-giving-different-output — Niel Godfrey Pablo Ponciano, Sep 05 '21 at 13:36

score 1 · Accepted Answer · answered Sep 05 '21 at 13:53

1

One item tuple, remember the commma:

thistuple = ("n",)
print(type(thistuple))

output:

<class 'tuple'>

but:

#NOT a tuple
thistuple = ("n")
print(type(thistuple))

output:

<class 'str'>

answered Sep 05 '21 at 13:53

Salio

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Python `in` keyword gives false positivies

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