input: Write a function to calculate the sum of all values in a dictionary where the keys are strings and the values are integers. The function should return the total sum of these values. If the dictionary is empty, the function should return 0.
  assert compute_dict_sum({"a": 5, "b": 10, "c": 15})==30
  assert compute_dict_sum({"x": 7, "y": 13, "z": 6})==26
  assert compute_dict_sum({})==0
  assert compute_dict_sum({"single": 99})==99
  assert compute_dict_sum({"key1": 1, "key2": 2, "key3": 3, "key4": 4})==10
output: def compute_dict_sum(d):
      return sum(d.values())