code: def setup(self, float_dtype):
      x_dtype = self.x_dtype
      param_dtype = self.param_dtype
      eps = self.eps
      axis = self.axis
  
      optional_args = {}
      if eps is not None:
          optional_args["eps"] = eps
      if axis is not None:
          optional_args["axis"] = axis
      self.optional_args = optional_args
  
      if x_dtype == "float16" or param_dtype == "float16":
          self.check_forward_options.update(
              {"rtol": 1e-1, "atol": 1e-1}
          )
      else:
          self.check_forward_options.update(
              {"rtol": 1e-6, "atol": 1e-5}
          )
  
imports: import unittest
  import chainer
  import numpy
  import pytest
  import chainerx
  import chainerx.testing
  from chainerx_tests import array_utils
  from chainerx_tests import op_utils
label_desc: Use image node_id 1 for calling the TestFixedBatchNorm obj's underlying member method code with example usage: obj.setup(float_dtype) without return types