private void checkDocString(@NotNull PyFunction function) {
      final PyStringLiteralExpression docStringExpression = function.getDocStringExpression();
      if (docStringExpression != null) {
        PySignatureCacheManager manager = PySignatureCacheManager.getInstance(function.getProject());
        if (manager != null) {
          PySignature signature = manager.findSignature(function);
          if (signature != null) {
            checkParameters(function, docStringExpression, signature);
          }
        }
      }
    }
private void checkDocString(@NotNull PyFunction function)