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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def format(self, name=False, formatter=None, **kwargs):
 """ Render a string representation of the Index. """

        header = []
        if name:
            header.append(pprint_thing(self.name,
                                       escape_chars=('\t', '\r', '\n')) if
                          self.name is not None else '')

        if formatter is not None:
            return header + list(self.map(formatter))

        return self._format_with_header(header, **kwargs)