code: def test_unicode_input(self):
      x = pd.Series(
          [
              "Ángel Angel Ángel ángel",
          ],
      )
      expected = pd.Series([23])
      actual = self.primitive().get_function()(x)
      pd.testing.assert_series_equal(
          actual, expected, check_names=False
      )
  
file_path: featuretools/featuretools/tests/primitive_tests/natural_language_primitives_tests/test_num_characters.py
imports: import numpy
  import pandas
  from featuretools.primitives import NumCharacters
  from featuretools.tests.primitive_tests.utils import PrimitiveTestBase, find_applicable_primitives, valid_dfs
label_desc: Use image node_id 3 for calling the TestNumCharacters obj's underlying member method code with example usage: obj.test_unicode_input() without return types