code: def step(self, x, state, **kwargs):
      # x: [batch, d_input]
      if self.transposed:
          # expects: [batch, d_input, seq_len]
          return self.ff(x.unsqueeze(-1)).squeeze(-1), state
      else:
          return self.ff(x), state
  
file_path: espnet/espnet2/asr/state_spaces/ff.py
imports: from functools import partial
  from torch import nn
  from espnet2.asr.state_spaces.base import SequenceModule
  from espnet2.asr.state_spaces.components import DropoutNd, LinearActivation
label_desc: Use image node_id 3 for calling the FF obj's underlying member method code with example usage: obj.step(x, state) and returns: self,  state, self,  state