code: def train(
      self,
      batch_data,
      input_mapping_id="default",
      operations_id="default",
      losses_id="default",
      outputs_id="default",
  ):
      self._model_updated = True
      return self._model.train(
          batch_data=batch_data,
          input_mapping_id=input_mapping_id,
          operations_id=operations_id,
          losses_id=losses_id,
          outputs_id=outputs_id,
      )
  
file_path: openrec/openrec/tf1/fast_dot_product_server.py
imports: import numpy
  import tensorflow
  from termcolor import colored
  from openrec.tf1.recommenders import PMF
  from openrec.tf1.modules.extractions import LatentFactor
  import math
label_desc: Use image node_id 4 for calling the FastDotProductServer obj's underlying member method code with example usage: obj.train(batch_data, input_mapping_id, operations_id, losses_id, outputs_id) and returns: self