static String returnType(@NotNull PyFunction function) {
    if (function.getAnnotation() != null && function.getAnnotation().getValue() != null) {
      return function.getAnnotation().getValue().getText();
    }

    final PySignature signature = PySignatureCacheManager.getInstance(function.getProject()).findSignature(function);
    if (signature != null) {
      final String qualifiedName = signature.getReturnTypeQualifiedName();
      if (qualifiedName != null) return qualifiedName;
    }

    return PyNames.OBJECT;
  }
static String returnType(@NotNull PyFunction function)