code: def get_metadata_version(self):
      mv = getattr(self, "metadata_version", None)
      if mv is None:
          mv = Version("2.1")
          self.metadata_version = mv
      return mv
  
imports: import os
  import stat
  import textwrap
  from email import message_from_file
  from email.message import Message
  from tempfile import NamedTemporaryFile
  from typing import Optional, List
  from distutils.util import rfc822_escape
  from .None import _normalization, _reqs
  from .extern.packaging.markers import Marker
  from .extern.packaging.requirements import Requirement
  from .extern.packaging.version import Version
  from .warnings import SetuptoolsDeprecationWarning
label_desc: Use image node_id 1 for calling a global function with example usage: get_metadata_version() and returns: mv