Execute a wheel function through the master network interface (eauth).

def master_call(self, **kwargs):
        '''
        Execute a wheel function through the master network interface (eauth).
        '''
        load = kwargs
        load['cmd'] = 'wheel'
        interface = self.opts['interface']
        if interface == '0.0.0.0':
            interface = '127.0.0.1'
        master_uri = 'tcp://{}:{}'.format(
            salt.utils.zeromq.ip_bracket(interface),
            six.text_type(self.opts['ret_port'])
        )
        channel = salt.transport.client.ReqChannel.factory(self.opts,
                                                           crypt='clear',
                                                           master_uri=master_uri,
                                                           usage='master_call')
        try:
            ret = channel.send(load)
        finally:
            channel.close()
        if isinstance(ret, collections.Mapping):
            if 'error' in ret:
                salt.utils.error.raise_error(**ret['error'])
        return ret