class_docstr: Represents an attention mask.
class_docstr_tok: ["Represents","an","attention","mask","."]
docstr: Materialize the attention mask tensor.
docstr_tok: ["Materialize","the","attention","mask","tensor","."]
code: def materialize(self) -> Tensor:
      """Materialize the attention mask tensor."""
      if self.materialized is None:
          self.materialized = self._do_materialize()
  
      return self.materialized
  
imports: from abc import ABC, abstractmethod
  from typing import Optional, Protocol, final
  import torch
  from torch import Tensor
  from fairseq2.nn.incremental_state import IncrementalStateBag
  from fairseq2.typing import DataType, Device, finaloverride
label_desc: Use image node_id 2 for calling the AttentionMask obj's underlying member method code with example usage: obj.materialize() and returns: self