code: def build_client_model(feature_num):
      inputs = Input(shape=(feature_num))
      outputs = Dense(1)(inputs)
      return Model(
          inputs=inputs, outputs=outputs, name="vfl_client_model"
      )
  
file_path: BigDL/python/ppml/example/tensorflow_nn_lr/tensorflow_nn_lr_2.py
imports: import logging
  import numpy
  import pandas
  import click
  import tensorflow
  from tensorflow import Tensor
  from tensorflow.keras.layers import Dense
  from tensorflow.keras import Model, Input
  from bigdl.ppml.fl.estimator import Estimator
  from bigdl.ppml.fl.nn.fl_context import init_fl_context
  from bigdl.ppml.fl.psi.psi_client import PSI
label_desc: Use image node_id 1 for calling a global function with example usage: build_client_model(feature_num) and returns: Model