@Nullable
  static PythonPathCache getPathCache(PsiElement foothold) {
    PythonPathCache cache = null;
    final Module module = ModuleUtilCore.findModuleForPsiElement(foothold);
    if (module != null) {
      cache = PythonModulePathCache.getInstance(module);
    }
    else {
      final Sdk sdk = PyBuiltinCache.findSdkForFile(foothold.getContainingFile());
      if (sdk != null) {
        cache = PythonSdkPathCache.getInstance(foothold.getProject(), sdk);
      }
    }
    return cache;
  }
@Nullable
  static PythonPathCache getPathCache(PsiElement foothold)