code: def _timebin_self_attention_fn(self, use_reference_code=False):
      return functools.partial(
          tl.SelfAttention,
          attention_dropout=0.05,
          chunk_len=64,
          n_chunks_before=1,
          n_parallel_heads=1,
          use_reference_code=use_reference_code,
      )
  
file_path: trax/trax/models/reformer/reformer_test.py
imports: import functools
  from absl.testing import absltest
  from absl.testing import parameterized
  import gin
  import numpy
  from trax import fastmath
  from trax import layers
  from trax import shapes
  from trax.models.reformer import reformer
label_desc: Use image node_id 3 for calling the ReformerTest obj's underlying member method code with example usage: obj._timebin_self_attention_fn(use_reference_code) and returns: functools