input: Write a function to compute the sum of all values in a given dictionary with string keys and integer values.
  
  assert compute_dict_sum({"a": 5, "b": 10, "c": 15})==30
  assert compute_dict_sum({"x": 7, "y": 14, "z": 21})==42
  assert compute_dict_sum({})==0
  assert compute_dict_sum({"a": 3, "b": 6, "c": 9})==18
  assert compute_dict_sum({"key1": 2, "key2": 4, "key3": 6})==12
output: def compute_dict_sum(d):
      return sum(d.values())