code: def test_copy(self):
      # train model #1
      metric = Metric({"name": "logloss"})
      cat = CatBoostAlgorithm(self.params)
      cat.fit(self.X, self.y)
      y_predicted = cat.predict(self.X)
      loss = metric(self.y, y_predicted)
      # create model #2
      cat2 = CatBoostAlgorithm(self.params)
      # model #2 is initialized in constructor
      self.assertTrue(cat2.model is not None)
      # do a copy and use it for predictions
      cat2 = cat.copy()
      self.assertEqual(type(cat), type(cat2))
      y_predicted = cat2.predict(self.X)
      loss2 = metric(self.y, y_predicted)
      self.assertEqual(loss, loss2)
  
imports: import unittest
  import tempfile
  import json
  import copy
  import numpy
  import pandas
  import os
  from numpy.testing import assert_almost_equal
  from sklearn import datasets
  from supervised.algorithms.catboost import CatBoostAlgorithm, additional
  from supervised.utils.metric import Metric
  import tempfile
label_desc: Use image node_id 4 for calling the CatBoostAlgorithmTest obj's underlying member method code with example usage: obj.test_copy() without return types