Fetch flow's data and return proper Flow object.

def Get(self):
    """Fetch flow's data and return proper Flow object."""

    args = flow_pb2.ApiGetFlowArgs(
        client_id=self.client_id, flow_id=self.flow_id)
    data = self._context.SendRequest("GetFlow", args)
    return Flow(data=data, context=self._context)