Question

I have this code

list = ['a','b','c']

if 'b' in list:
   return "found it"
return "not found"

Now, how does this work? Does it traverse the whole list comparing the element? Does it use some kind of hash function?

Also, is it the same for this code?

list.index('b')

Answer 1

in uses the method __contains__. Each container type implements it differently. For a list, it uses linear search. For a dict, it uses a hash lookup.