input: Write a python function to multiply each element in a list by 10.
  assert multiply_by_10([1, 2, 3, 4]) == [10, 20, 30, 40]
  assert multiply_by_10([5, 6, 7]) == [50, 60, 70]
  assert multiply_by_10([0, -1, -2]) == [0, -10, -20]
output: def multiply_by_10(lst):
      return [x * 10 for x in lst]