input: Write a function to sum up all the values in a given dictionary (string → integer). If the dictionary is empty, return 0.
  def compute_dict_sum(input_dict):
      result = 0
      for val in input_dict.values():
          result += val
      return result
  assert compute_dict_sum({"a": 5, "b": 10, "c": 15})==30
  assert compute_dict_sum({"x": 2, "y": 4, "z": 6})==12
  assert compute_dict_sum({})==0
output: def compute_dict_sum(input_dict):
      result = 0
      for val in input_dict.values():
          result += val
      return result