code: def setup(self):
      super().setup()
      (in_dtype,) = self.in_dtypes
      if in_dtype == "float16":
          self.check_forward_options.update(
              {"rtol": 1e-2, "atol": 1e-2}
          )
          self.check_backward_options.update(
              {"rtol": 1e-2, "atol": 1e-2}
          )
          self.check_double_backward_options.update(
              {"rtol": 1e-2, "atol": 1e-2}
          )
  
imports: import chainer
  import numpy
  import pytest
  import chainerx
  import chainerx.testing
  from chainerx_tests import array_utils
  from chainerx_tests import math_utils
  from chainerx_tests import op_utils
label_desc: Use image node_id 1 for calling the TestNansum obj's underlying member method code with example usage: obj.setup() without return types