input: Write a python function to create a dictionary from a list of keys where the values are their corresponding indices.
  assert create_dict(['foo', 'bar', 'baz', 'qux']) == {'foo': 0, 'bar': 1, 'baz': 2, 'qux': 3}
  assert create_dict(['apple', 'banana', 'cherry']) == {'apple': 0, 'banana': 1, 'cherry': 2}
  assert create_dict([]) == {}
output: def create_dict(keys):
      return {key: index for index, key in enumerate(keys)}