code: def _tolerance_by_dtype(dtype):
      """Returns the expected tolerance based on dtype."""
      return 1e-8 if dtype == np.float64 else 5e-3
  
imports: from absl.testing import parameterized
  import numpy
  import tensorflow.compat.v2
  import tf_quant_finance
  from tensorflow.python.framework import test_util
  from tf_quant_finance.models.geometric_brownian_motion import geometric_brownian_motion_test_utils
  from tf_quant_finance.models.geometric_brownian_motion import univariate_geometric_brownian_motion
label_desc: Use image node_id 1 for calling a global function with example usage: _tolerance_by_dtype(dtype) and returns: unknown