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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 raise_for_response(self, responses):
 """ Constructs appropriate exception from list of responses and raises it. """

        exception_messages = [self.client.format_exception_message(response) for response in responses]
        if len(exception_messages) == 1:
            message = exception_messages[0]
        else:
            message = "[%s]" % ", ".join(exception_messages)
        raise PostmarkerException(message)