code: def _glibc_version_string():
      # type: () -> Optional[str]
      # Returns glibc version string, or None if not using glibc.
      return (
          _glibc_version_string_confstr()
          or _glibc_version_string_ctypes()
      )
  
imports: from __future__ import absolute_import
  import distutils.util
  import collections
  import logging
  import os
  import platform
  import re
  import struct
  import sys
  import sysconfig
  import warnings
  from ._typing import TYPE_CHECKING, cast
label_desc: Use image node_id 16 for calling a global function with example usage: _glibc_version_string() and returns: unknown