input: Write a python function to merge two dictionaries.
  assert merge_dicts({'a': 1, 'b': 2, 'c': 3}, {'d': 4, 'e': 5, 'f': 6}) == {'a': 1, 'b': 2, 'c': 3, 'd': 4, 'e': 5, 'f': 6}
  assert merge_dicts({'x': 10, 'y': 20}, {'y': 30, 'z': 40}) == {'x': 10, 'y': 30, 'z': 40}
  assert merge_dicts({}, {'g': 7, 'h': 8}) == {'g': 7, 'h': 8}
output: def merge_dicts(dict1, dict2):
      merged_dict = dict1.copy()
      merged_dict.update(dict2)
      return merged_dict