code: def test_positive_lower(
      env_lower: float, override_lower: Optional[float]
  ) -> None:
      expected_lower = override_lower or env_lower
      with as_context(
          Config(
              positive_bijector="softplus", positive_minimum=env_lower
          )
      ):
          bijector = positive(lower=override_lower)
          assert isinstance(bijector, tfp.bijectors.Chain)
          assert np.isclose(bijector.bijectors[0].shift, expected_lower)
  
file_path: GPflow/tests/gpflow/utilities/test_bijectors.py
imports: from typing import Optional, Type
  import numpy
  import pytest
  import tensorflow
  import tensorflow_probability
  from gpflow.config import Config, as_context
  from gpflow.utilities import positive, triangular, triangular_size
label_desc: Use image node_id 1 for calling a global function with example usage: test_positive_lower(env_lower, override_lower) without return types