code: def compare(self, primitive_initiated, test_cases, answers):
      primitive_func = primitive_initiated.get_function()
      primitive_answers = primitive_func(test_cases)
      return np.testing.assert_array_equal(answers, primitive_answers)
  
imports: import numpy
  import pandas
  from featuretools.primitives import CountString
  from featuretools.tests.primitive_tests.utils import PrimitiveTestBase, find_applicable_primitives, valid_dfs
label_desc: Use image node_id 1 for calling the TestCountString obj's underlying member method code with example usage: obj.compare(primitive_initiated, test_cases, answers) and returns: np