code: def GetParserObjects(cls, parser_filter_expression=None):
      
      includes, excludes = cls._GetParserFilters(parser_filter_expression)
  
      parser_objects = {}
      for parser_name, parser_class in iter(cls._parser_classes.items()):
        # If there are no includes all parsers are included by default.
        if not includes and parser_name in excludes:
          continue
  
        if includes and parser_name not in includes:
          continue
  
        parser_object = parser_class()
        if parser_class.SupportsPlugins():
          plugin_includes = None
          if parser_name in includes:
            plugin_includes = includes[parser_name]
  
          parser_object.EnablePlugins(plugin_includes)
  
        parser_objects[parser_name] = parser_object
  
      return parser_objects
docs: Retrieves the parser objects.
  
      Args:
        parser_filter_expression (Optional[str]): parser filter expression,
            where None represents all parsers and plugins.
  
      Returns:
        dict[str, BaseParser]: parsers per name.