code: def test_invalid_two_duplicates(self):
      known_labels = ["A", "B", "C"]
      passed_labels = ["A", "B", "A", "B"]
      arg_name = "true_labels"
  
      with self.assertRaises(ValueError) as context:
          skplt.validate_labels(known_labels, passed_labels, arg_name)
  
      msg = "The following duplicate labels were passed into true_labels: A, B"
      self.assertEqual(msg, str(context.exception))
  
imports: from __future__ import absolute_import
  import unittest
  import scikitplot.plotters
  from sklearn.datasets import load_iris
  from sklearn.decomposition import PCA
  import numpy
  import matplotlib.pyplot
label_desc: Use image node_id 4 for calling the TestValidateLabels obj's underlying member method code with example usage: obj.test_invalid_two_duplicates() without return types