code: def test_glibc_version_string_confstr(monkeypatch):
      monkeypatch.setattr(
          os, "confstr", lambda x: "glibc 2.20", raising=False
      )
      assert _glibc_version_string_confstr() == "2.20"
  
imports: import os
  import pathlib
  import platform
  import sys
  import types
  import warnings
  import pretend
  import pytest
  from packaging import _manylinux
  from packaging._manylinux import _get_glibc_version, _glibc_version_string, _glibc_version_string_confstr, _glibc_version_string_ctypes, _is_compatible, _parse_elf, _parse_glibc_version
label_desc: Use image node_id 8 for calling a global function with example usage: test_glibc_version_string_confstr(monkeypatch) without return types