My implementation of merging two sorted lists in linear time - what could be improved?

Question

Fromg Google\'s Python Class:

E. Given two lists sorted in increasing order, create and return a merged
list of all the elements in sorted order. You may mod         


        

Answer 1

This solution runs in linear time and without editing l1 and l2:

def merge(l1, l2):
  m, m2 = len(l1), len(l2)
  newList = []
  l, r = 0, 0
  while l < m and r < m2:
    if l1[l] < l2[r]:
      newList.append(l1[l])
      l += 1
    else:
      newList.append(l2[r])
      r += 1
  return newList + l1[l:] + l2[r:]