python - What's wrong with the IF some words IN a string -

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• compare multiple variables same value in “if” in python? 7 answers

how check string specific characters? find link useful. what's wrong codes?

string = "a17_b_c_s.txt"  if ("m.txt" , "17") in string:     print true else:     print false 

and answer comes out

true 

this because and evaluates 17 in stringlist. and evaluates 17 because of short circuiting.

>>> "m.txt" , "17" '17' 

python evaluates non empty strings value true. hence, m.txt evaluates true, value of expression depends on second value returned(17) , found in stringlist. (why? when and performed true value, value of expression depends on second value, if it's false, value of expression false, else, it's true.)

you need change expression

if "m.txt" in stringlist , "17" in stringlist:     #... 

or use builtin all()

if all(elem in stringlist elem in ["m.txt", "17"]):     #...