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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 _read_ip_hextet(self):
 """Read first four hextets of IPv6."""

        _htet = self._read_fileng(4).hex()
        _vers = _htet[0]                    # version number (6)
        _tcls = int(_htet[0:2], base=16)    # traffic class
        _flow = int(_htet[2:], base=16)     # flow label

        return (_vers, _tcls, _flow)