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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 _build_raw_headers(self, headers: Dict) -> Tuple: """ Convert a dict of headers to a tuple of tuples Mimics the format of ClientResponse. """

        raw_headers = []
        for k, v in headers.items():
            raw_headers.append((k.encode('utf8'), v.encode('utf8')))
        return tuple(raw_headers)