code: def test_addmm(self, in_features, out_features, backend):
      model = nn.Linear(in_features, out_features)
      run_compare_torch((1, in_features), model, backend=backend)
  
imports: import sys
  from coremltools.converters.mil import testing_reqs
  from coremltools.converters.mil.testing_reqs import *
  from .testing_utils import *
label_desc: Use image node_id 1 for calling the TestLinear obj's underlying member method code with example usage: obj.test_addmm(in_features, out_features, backend) without return types