code: def not_supported_reasons(cls, d: Inputs) -> List[str]:
      reasons = super(AttentionBwOpBase, cls).not_supported_reasons(d)
      if (
          isinstance(d.attn_bias, torch.Tensor)
          and d.attn_bias.requires_grad
          and not cls.SUPPORTS_ATTN_BIAS_GRAD
      ):
          reasons.append(
              "Computing the bias gradient is not supported (attn_bias.requires_grad = True)"
          )
  
      return reasons
  
imports: import math
  from dataclasses import dataclass
  from functools import partial
  from typing import Any, Callable, List, Mapping, Optional, Set, Tuple, Type, Union
  import torch
  from ..._cpp_lib import _built_with_cuda
  from ..common import BaseOperator
  from .attn_bias import AttentionBias, BlockDiagonalMask, LowerTriangularMask, LowerTriangularMaskWithTensorBias
label_desc: Use image node_id 1 for calling the AttentionBwOpBase obj's underlying member method code with example usage: obj.not_supported_reasons(cls, d) and returns: reasons