code: def is_source_release(path):
      return os.path.exists(os.path.join(path, "PKG-INFO"))
  
imports: import os
  import subprocess
  import sys
  import contextlib
  from distutils.command.build_ext import build_ext
  from distutils.sysconfig import get_python_inc
  import distutils.util
  from distutils import ccompiler, msvccompiler
  from setuptools import Extension, setup, find_packages
label_desc: Use image node_id 4 for calling a global function with example usage: is_source_release(path) and returns: os