code: def __init__(self, input_size):
      super().__init__()
      self.__scale = None
      self.net = None
  
      # base distribution for calculation of log prob under the model
      self.register_buffer("base_dist_mean", torch.zeros(input_size))
      self.register_buffer("base_dist_var", torch.ones(input_size))
  
imports: import copy
  import math
  import torch
  import torch.nn
  import torch.nn.functional
  from torch.distributions import Normal
label_desc: Use image node_id 1 to create a new Flow object from inherited base classes: nn with example: obj = Flow(input_size)