code: def upsample_factor(self):
      return 2 ** sum(1 for block in self.blocks if block.upsample)
  
imports: import math
  from functools import partial
  from math import log2
  from typing import List
  import torch
  import torch.nn.functional
  from einops import rearrange
  from kornia.filters import filter2d
  from nemo.collections.tts.parts.utils.helpers import mask_sequence_tensor
label_desc: Use image node_id 3 for calling the Generator obj's underlying member method code with example usage: obj.upsample_factor() and returns: unknown