class_docstr: Most tests done in the base class LinearOperatorDerivedClassTest.
code: def test_convert_variables_to_tensors(self):
      col = variables_module.Variable([1.0])
      row = variables_module.Variable([1.0])
      operator = linear_operator_toeplitz.LinearOperatorToeplitz(
          col, row, is_self_adjoint=True, is_positive_definite=True
      )
      with self.cached_session() as sess:
          sess.run([x.initializer for x in operator.variables])
          self.check_convert_variables_to_tensors(operator)
  
imports: import contextlib
  import numpy
  import scipy.linalg
  from tensorflow.python.eager import backprop
  from tensorflow.python.framework import dtypes
  from tensorflow.python.framework import test_util
  from tensorflow.python.ops import array_ops
  from tensorflow.python.ops import math_ops
  from tensorflow.python.ops import variables
  from tensorflow.python.ops.linalg import linalg
  from tensorflow.python.ops.linalg import linear_operator_test_util
  from tensorflow.python.ops.linalg import linear_operator_toeplitz
  from tensorflow.python.platform import test
label_desc: Use image node_id 8 for calling the LinearOperatorToeplitzTest obj's underlying member method code with example usage: obj.test_convert_variables_to_tensors() without return types