class_docstr: Handles metadata supplied in configuration files.
class_docstr_tok: ["Handles","metadata","supplied","in","configuration","files","."]
docstr: Metadata item name to parser function mapping.
docstr_tok: ["Metadata","item","name","to","parser","function","mapping","."]
code: def parsers(self):
      """Metadata item name to parser function mapping."""
      raise NotImplementedError(
          "%s must provide .parsers property" % self.__class__.__name__
      )
  
imports: import contextlib
  import functools
  import os
  from collections import defaultdict
  from functools import partial
  from functools import wraps
  from typing import TYPE_CHECKING, Callable, Any, Dict, Generic, Iterable, List, Optional, Set, Tuple, TypeVar, Union
  from ..errors import FileError, OptionError
  from ..extern.packaging.markers import default_environment
  from ..extern.packaging.requirements import InvalidRequirement, Requirement
  from ..extern.packaging.specifiers import SpecifierSet
  from ..extern.packaging.version import InvalidVersion, Version
  from ..warnings import SetuptoolsDeprecationWarning
  from .None import expand
label_desc: Use image node_id 3 for calling the ConfigHandler obj's underlying member method code with example usage: obj.parsers() without return types