Python: (sub) String equivalence vs List fast membership testing

Question

Can somebody explain to me the following (python 2.7)

Two string numbers, from a parsed file:

'410.9' '410.9 ' (Notice the trailing space)

A_LIST = ['410.9 ']

'410.9' in '410.9 '
True

'410.9' in A_LIST
False

No problem working around this - just trying to understand why it is so.

Thanks!

Answer 1

in with two strings checks or a substring, whereas in with a list checks for membership.

What you want is something like [x for x in A_LIST if '419' in x]