OR behaviour in python:

Question

I have written the following piece of code, all i want to do is print a yes for if the number passed is a string representation of 1, 0 or 2 and for everything else a false:

Answer 1

Because every expression between an or is evaluated as a boolean expression.

if True evaluates to True, if 1: evaluates to True, if "0": evaluates to True.

So what you wrote is more or less the equivalent to:

if number is "1":
    print "Yes"
elif "0":
    print "Yes"
elif "2":
    print "Yes"
else:
     print "no"

You should have written if number is "1" or number is "0" or number "2": or, more pythonic: if number in ("1", "0", "2"):