Python: List Comprehension: Alternate

Write a function that takes two lists lst1 and lst2 and return another list whose elements are elements of lst1 and lst2 alternately. The input lists could be in different sizes.


alternate([1,2,3,4,5], [6,7,8]) -> [1,6,2,7,3,8,4,5]
alternate([1,2,3,4,5], []) -> [1,2,3,4,5]

Test 1    

Test 2    

Test 3    

Test 4