def echo_stdin(self, input_, output):
        return (not self.using_pty) and isatty(input_)
check if the manager is derived from PolymorphicManager
dataset/ETHPy150Open pyinvoke/invoke/invoke/runners.py/Runner.echo_stdin--crossover with--dataset/ETHPy150Open chrisglass/django_polymorphic/polymorphic/base.py/PolymorphicModelBase.validate_model_manager