Write a function takes as input two lists [a_1,...,a_n], [b_1,...,b_n] and returns [a_1+b_1,...,a_n+b_n].
def sum_list(lst1,lst2):
  res_list = [lst1[i] + lst2[i] for i in range(len(lst1))] 
  return res_list
assert sum_list([10,20,30],[15,25,35])==[25,45,65] assert sum_list([1,2,3],[5,6,7])==[6,8,10] assert sum_list([15,20,30],[15,45,75])==[30,65,105]