code: def test_non_unitary_anonymous_axes_raises_error(self) -> None:
      axes_lengths: Dict[str, int] = {}
  
      left_non_unitary_axis = "a 2 -> 1 1 a"
      left, right = parse_pattern(left_non_unitary_axis, axes_lengths)
      with self.assertRaises(ValueError):
          validate_rearrange_expressions(left, right, axes_lengths)
  
      right_non_unitary_axis = "1 1 a -> a 2"
      left, right = parse_pattern(right_non_unitary_axis, axes_lengths)
      with self.assertRaises(ValueError):
          validate_rearrange_expressions(left, right, axes_lengths)
  
imports: from typing import Any, Callable, Dict
  from unittest import mock
  from functorch.einops._parsing import AnonymousAxis, ParsedExpression, parse_pattern, validate_rearrange_expressions, _ellipsis
  from torch.testing._internal.common_utils import TestCase, run_tests
label_desc: Use image node_id 2 for calling the TestValidateRearrangeExpressions obj's underlying member method code with example usage: obj.test_non_unitary_anonymous_axes_raises_error() without return types