code: def test_unicode_input(self):
      x = pd.Series(
          [
              "@Ángel @Æ @ĘÁÊÚ",
              "@@@@Āndandandandand@",
              "andorandorand @32309",
              "example@gmail.com",
              "@example-20329",
          ],
      )
      expected = [3.0, 0.0, 1.0, 0.0, 1.0]
      actual = self.primitive().get_function()(x)
      np.testing.assert_array_equal(actual, expected)
  
file_path: featuretools/featuretools/tests/primitive_tests/natural_language_primitives_tests/test_number_of_mentions.py
imports: import numpy
  import pandas
  from featuretools.primitives import NumberOfMentions
  from featuretools.tests.primitive_tests.utils import PrimitiveTestBase, find_applicable_primitives, valid_dfs
label_desc: Use image node_id 2 for calling the TestNumberOfMentions obj's underlying member method code with example usage: obj.test_unicode_input() without return types