การเขียน docstring

# Complete the function's docstring
def tokenize(text, regex=r'[a-zA-z]+'):
  """Split text into tokens using a regular expression

  :____ text: text to be tokenized
  :param ____: regular expression used to match tokens using re.findall 
  :____: a list of resulting tokens

  >>> ____('the rain in spain')
  ____
  """
  return re.findall(regex, text, flags=re.IGNORECASE)

# Print the docstring
help(tokenize)