Most pythonic way to interleave two strings

Question

What\'s the most pythonic way to mesh two strings together?

For example:

Input:

u = \'ABCDEFGHIJKLMNOPQRSTUVWXYZ\'
l = \'abcdefghijklmnopqrst         


        

Answer 1

Just to add another, more basic approach:

st = ""
for char in u:
    st = "{0}{1}{2}".format( st, char, l[ u.index( char ) ] )