(self, cl, req, res)
Called to handle /meta/handshake. No default behavior or expected 
        return value.
Called to handle /meta/handshake. No default behavior or expected 
        return value.
Called to handle / meta / handshake . No default behavior or expected return value .
def on_handshake(self, cl, req, res):
        '''
        Called to handle /meta/handshake. No default behavior or expected 
        return value.
        '''
        pass
def on_handshake ( self , cl , req , res ) : pass