def check_backslashes(self, definition, docstring):
        r'''D301: Use r""" if any backslashes in a docstring.

        Use r"""raw triple double quotes""" if you use any backslashes
        (\) in your docstrings.

        '''
        # Just check that docstring is raw, check_triple_double_quotes
        # ensures the correct quotes.
        if docstring and '\\' in docstring and not docstring.startswith(
                ('r', 'ur')):
            return violations.D301()
r'''D301: Use r""" if any backslashes in a docstring.

        Use r"""raw triple double quotes""" if you use any backslashes
        (\) in your docstrings.