code: def hacking_docstring_start_space(physical_line, previous_logical, tokens):
      r
      docstring = is_docstring(tokens, previous_logical)
      if docstring:
          start, start_triple = _find_first_of(docstring, START_DOCSTRING_TRIPLE)
          if docstring[len(start_triple)] == ' ':
              # docstrings get tokenized on the last line of the docstring, so
              # we don't know the exact position.
              return (0, "H401: docstring should not start with"
                      " a space")
docs: r"""Check for docstring not starting with space.
  
      OpenStack HACKING guide recommendation for docstring:
      Docstring should not start with space
  
      Okay: def foo():\n    '''This is good.'''
      Okay: def foo():\n    r'''This is good.'''
      Okay: def foo():\n    a = ''' This is not a docstring.'''
      Okay: def foo():\n    pass\n    ''' This is not.'''
      H401: def foo():\n    ''' This is not.'''
      H401: def foo():\n    r''' This is not.'''