docstr: Returns the number of input variables
docstr_tok: ["Returns","the","number","of","input","variables"]
code: def n_inputs(self):
      """Returns the number of input variables"""
      return self.__n_inputs
  
file_path: OMLT/src/omlt/gbt/model.py
label_desc: Use image node_id 3 for calling the GradientBoostedTreeModel obj's underlying member method code with example usage: obj.n_inputs() and returns: self