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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 _no_more_pads(self, element):
 """The callback for GstElement's "no-more-pads" signal. """

        # Sent when the pads are done adding (i.e., there are no more
        # streams in the file). If we haven't gotten at least one
        # decodable stream, raise an exception.
        if not self._got_a_pad:
            self.read_exc = NoStreamError()
            self.ready_sem.release()