def check_triple_double_quotes(self, definition, docstring):
        r'''D300: Use """triple double quotes""".

        For consistency, always use """triple double quotes""" around
        docstrings. Use r"""raw triple double quotes""" if you use any
        backslashes in your docstrings. For Unicode docstrings, use
        u"""Unicode triple-quoted strings""".

        Note: Exception to this is made if the docstring contains
              """ quotes in its body.

        '''
        if docstring:
            if '"""' in ast.literal_eval(docstring):
                # Allow ''' quotes if docstring contains """, because
                # otherwise """ quotes could not be expressed inside
                # docstring. Not in PEP 257.
                regex = re(r"[uU]?[rR]?'''[^'].*")
            else:
                regex = re(r'[uU]?[rR]?"""[^"].*')

            if not regex.match(docstring):
                illegal_matcher = re(r"""[uU]?[rR]?("+|'+).*""")
                illegal_quotes = illegal_matcher.match(docstring).group(1)
                return violations.D300(illegal_quotes)
r'''D300: Use """triple double quotes""".

        For consistency, always use """triple double quotes""" around
        docstrings. Use r"""raw triple double quotes""" if you use any
        backslashes in your docstrings. For Unicode docstrings, use
        u"""Unicode triple-quoted strings""".

        Note: Exception to this is made if the docstring contains
              """ quotes in its body.