class_docstr: The Two Tower model used for recommendation retrieval.
  
  # Arguments
  user_col_info: user column information.
  item_col_info: item column information.
  hidden_layers: Units of hidden layers for each tower.
                 Tuple of positive int. Default is [1024, 512, 128].
code: def __init__(
      self, user_col_info, item_col_info, hidden_layers=[1024, 512, 128]
  ):
      self.user_col_info = user_col_info
      self.item_col_info = item_col_info
      self.hidden_layers = hidden_layers
  
file_path: analytics-zoo/pyzoo/zoo/examples/friesian/two_tower/model.py
imports: from zoo.pipeline.api.keras.layers import *
  from tensorflow.keras.layers import Input, Embedding, Dense, Flatten, concatenate, Lambda
  import tensorflow
label_desc: Use image node_id 1 to create a new TwoTowerModel object from inherited base classes: object with example: obj = TwoTowerModel(user_col_info, item_col_info, hidden_layers)