class_docstr: Test for validation and exceptions
docstr: Test that an error is raised if the transform
  is applied to an unknown object
docstr_tok: ["Test","that","an","error","is","raised","if","the","transform","is","applied","to","an","unknown","object"]
code: def test_unknown_object(self):
      """Test that an error is raised if the transform
      is applied to an unknown object"""
  
      @qml.op_transform
      def my_transform(op):
          return op.name
  
      with pytest.raises(
          OperationTransformError,
          match="Input is not an Operator, tape, QNode, or quantum function",
      ):
          my_transform(5)(5)
  
imports: import pytest
  import pennylane
  from pennylane import numpy
  from pennylane.transforms.op_transforms import OperationTransformError
label_desc: Use image node_id 3 for calling the TestValidation obj's underlying member method code with example usage: obj.test_unknown_object() and returns: op