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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 get_response(self, environ=None):
 """Get a list of headers."""

        response = super(SameContentException, self).get_response(
            environ=environ
        )
        if self.etag is not None:
            response.set_etag(self.etag)
        if self.last_modified is not None:
            response.headers['Last-Modified'] = http_date(self.last_modified)
        return response