input: Write a function to create a Python dictionary from two given lists. If the lengths of the two lists are not equal, return an empty dictionary.
  assert create_dict(['a', 'b', 'c'], [1, 2, 3])=={'a': 1, 'b': 2, 'c': 3}
  assert create_dict(['a', 'b', 'c'], [1, 2, 3, 4])=={}
  assert create_dict([], [1, 2, 3])=={}
  assert create_dict(['a', 'b'], [])=={}
  assert create_dict([], [])=={}
output: def create_dict(keys, values):
      if len(keys) != len(values):
          return {}
      return dict(zip(keys, values))