code: def forward(self, input):
      return self.val + input
  
file_path: ray/python/ray/serve/tests/test_deployment_graph_ingress.py
imports: import sys
  import pytest
  from ray import serve
  from ray.serve._private.deployment_graph_build import build
  from ray.serve._private.deployment_graph_build import get_and_validate_ingress_deployment
label_desc: Use image node_id 2 for calling the Model obj's underlying member method code with example usage: obj.forward(input) and returns: unknown