input: Write a function to calculate the total sum of all integers in a list that are divisible by 3. If the list is empty, return 0.
  assert divisibleBy3([4, 6, 17, 24, 5, 9]) == 39
  assert divisibleBy3([1, 2, 3, 4, 5]) == 3
  assert divisibleBy3([3, 6, 9, 12, 15]) == 45
  assert divisibleBy3([1, 2, 4, 5, 7]) == 0
  assert divisibleBy3([]) == 0
output: def divisibleBy3(lst):
      return sum(x for x in lst if x % 3 == 0)