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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 encode(self):
 """Encode this stream as a packed 16-bit unsigned integer. Returns: int: The packed encoded stream """


        match_id = self.match_id
        if match_id is None:
            match_id = (1 << 11) - 1

        return (self.match_type << 12) | DataStreamSelector.SpecifierEncodings[self.match_spec] | match_id