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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 end_state(self):
 """ Wrap things up and add any final string content. """


        # Make sure we append any trailing text
        if self.str_begin != len(self.format):
            if len(self.state) > 1 or self.state[-1] != 'string':
                self.fmt.append_text(
                    "(Bad format string; ended in state %r)" % self.state[-1])
            else:
                self.fmt.append_text(self.format[self.str_begin:])

        # Convenience return
        return self.fmt