text: """Module to test online sources parsers."""
  import pytest
  from geniepy.datamgmt.parsers import BaseParser, ClassifierParser
  import tests.testdata as td
  from tests.resources.mock import TEST_CHUNKSIZE
  
  
  VALID_DF = td.CLSFR_VALID_DF
  INVALID_DF = td.CLSFR_INVALID_DF
  
  
  class TestClassifierParser:
      """Pytest CTD Parser class."""
  
      parser: BaseParser = ClassifierParser()
  
      def test_constructor(self):
          """Ensure scraper obj constructed successfully."""
          assert self.parser is not None
  
      @pytest.mark.parametrize("payload", INVALID_DF)
      def test_invalid_payload(self, payload):
          """Test invalid dataframe."""
          # Should return list with errors
          assert self.parser.validate(payload)
  
      @pytest.mark.parametrize("payload", VALID_DF)
      def test_valid_payload(self, payload):
          """Test valid dataframe."""
          # Should return empty list
          assert not self.parser.validate(payload)
  
      def test_parse_not_impl(self):
          """Parse method should not be implemented in classifier parser."""
          with pytest.raises(NotImplementedError):
              self.parser.parse(None)
  
      def test_fetch_not_impl(self):
          """Fetch method should not be implemented in classifier parser."""
          with pytest.raises(NotImplementedError):
              self.parser.fetch(TEST_CHUNKSIZE)
  