class_docstr: Helper class to create graphs to display memory
class_docstr_tok: ["Helper","class","to","create","graphs","to","display","memory"]
code: def _mask_forward_backward(
      cls, memory_traces: List[LayerMemoryTrace]
  ):
      mask_forwards = np.array([t.is_forward for t in memory_traces])
      return mask_forwards, ~mask_forwards
  
imports: from contextlib import contextmanager
  from dataclasses import dataclass
  from enum import auto, Enum
  from functools import lru_cache
  from typing import Dict, List, NamedTuple, Tuple, Union
  import numpy
  import torch
  import torch.nn
  from fairscale.nn import FullyShardedDataParallel
  from vissl.utils.visualize import matplotlib_figure_to_image
label_desc: Use image node_id 10 for calling the MemoryGraphCreator obj's underlying member method code with example usage: obj._mask_forward_backward(cls, memory_traces) and returns: mask_forwards,  unknown