code: def _q_sqrt_factory_fixture(request: SubRequest) -> QSqrtFactory:
      """
      When upgrading to Python 3.10, this can be replaced with a match-case statement.
      """
      if request.param == 0:
  
          def fn_0(
              n_inducing_points: int, num_latent_gps: int
          ) -> Optional[TensorType]:
              return None
  
          return fn_0
      elif request.param == 1:
  
          def fn_1(
              n_inducing_points: int, num_latent_gps: int
          ) -> Optional[TensorType]:
              # qsqrt: [M, L]
              return (
                  tf.random.normal(
                      (n_inducing_points, num_latent_gps),
                      dtype=tf.float64,
                  )
                  ** 2
              )
  
          return fn_1
      elif request.param == 2:
  
          def fn_2(
              n_inducing_points: int, num_latent_gps: int
          ) -> Optional[TensorType]:
              # qsqrt: [L, M, M]
              shape = (
                  num_latent_gps,
                  n_inducing_points,
                  n_inducing_points,
              )
              return tf.linalg.band_part(
                  tf.random.normal(shape, dtype=tf.float64), -1, 0
              )
  
          return fn_2
      else:
          raise NotImplementedError
  
imports: from typing import Any, Callable, DefaultDict, Optional, Set, Type, cast
  import numpy
  import pytest
  import tensorflow
  from _pytest.fixtures import SubRequest
  from check_shapes import check_shapes
  import gpflow
  import gpflow.ci_utils
  from gpflow.base import TensorType
  from gpflow.conditionals import conditional
  from gpflow.inducing_variables import InducingPoints, InducingVariables
  from gpflow.kernels import Kernel
  from gpflow.likelihoods import Gaussian
  from gpflow.mean_functions import Zero
  from gpflow.models.util import inducingpoint_wrapper
  from gpflow.posteriors import AbstractPosterior, FallbackIndependentLatentPosterior, FullyCorrelatedPosterior, GPRPosterior, IndependentPosteriorMultiOutput, IndependentPosteriorSingleOutput, LinearCoregionalizationPosterior, PrecomputeCacheType, SGPRPosterior, VGPPosterior, create_posterior
label_desc: Use image node_id 2 for calling a global function with example usage: _q_sqrt_factory_fixture(request) and returns: fn_0, None, fn_1, unknown, fn_2, tf