input: Write a function to compute the product of the sum of elements in a list and a given number.
  assert compute_product([1, 3, 5, 7], 3) == 48
  assert compute_product([2, 4, 6], 5) == 60
  assert compute_product([10, 20], 2) == 60
output: def compute_product(lst, num):
      return sum(lst) * num