def METHOD_NAME(self, handshaker):
    """Start a handshake operation.
    :param generator handshaker: A generator created by using one of the
        asynchronous handshake functions (i.e.
        :py:meth:`~.TLSConnection.handshakeServerAsync` , or
        handshakeClientxxx(..., async_=True).
    """
    try:
        self._checkAssert(0)
        self.handshaker = handshaker
        self._doHandshakeOp()
    except:
        self._clear()
        raise