docstr: Access this class's model attribute. TODO: investigate overloading.
          
docstr_tok: ["Access","this","class","'s","model","attribute",".","TODO",":","investigate","overloading","."]
code: def model(self):
      """Access this class's model attribute. TODO: investigate overloading."""
  
      if self.model is None:
          self.build_model()
  
      return self.model
  
imports: import csv
  from deepneuro.models.cost_functions import cost_function_dict
  from deepneuro.utilities.util import add_parameter, nifti_splitext
  from deepneuro.load.load import load
label_desc: Use image node_id 4 for calling the DeepNeuroModel obj's underlying member method code with example usage: obj.model() and returns: self