How to join two lists of 10 elements in python mixing the elements in a pattern?

Question

I need to ask for two lists of 10 elements each and return a list with 20 elements arranged with the first element from the first list, then the first element of the second list, then the second element of the first list, then the second element of the second list, and so on. I don't even know how to do this. Would you please help me? example:

list1=(1,2,3,4,5,6,7,8,9,10)
list2=(11,12,13,14,15,16,17,18,19,20)

expected result:

L=(1,11,2,12,3,13,4,14,5,15,6,16,7,17,8,18,9,19,10,20)

Answer 1

This is one way to do it:

z = zip(list1,list2)
L = []
for i in z:
  for x in i:
    L.append(x)
print L

Output:

[1, 11, 2, 12, 3, 13, 4, 14, 5, 15, 6, 16, 7, 17, 8, 18, 9, 19, 10, 20]