code: def test_add_scalar_double_backward(seed, val, ctx, func_name):
      # inplace test is not needed since grad does not depend on the inputs
      from nbla_test_utils import backward_function_tester
  
      rng = np.random.RandomState(seed)
      inputs = [rng.randn(2, 3).astype(np.float32)]
      backward_function_tester(
          rng,
          F.add_scalar,
          inputs=inputs,
          func_args=[val],
          func_kwargs={},
          atol_accum=1e-3,
          dstep=1e-3,
          ctx=ctx,
      )
  
file_path: nnabla/python/test/function/test_add_scalar.py
imports: import pytest
  import numpy
  import nnabla.functions
  import nnabla
  from nbla_test_utils import list_context
label_desc: Use image node_id 3 for calling a global function with example usage: test_add_scalar_double_backward(seed, val, ctx, func_name) without return types