# How to import actor that contains inherited class from other module?

**URL:** https://discuss.ray.io/t/how-to-import-actor-that-contains-inherited-class-from-other-module/4637
**Category:** Ray Core
**Created:** [January 10, 2022, 10:53am UTC](https://discuss.ray.io/t/how-to-import-actor-that-contains-inherited-class-from-other-module/4637 "2022-01-10T10:53:15Z")
**Posts on this page:** 3
**Page:** 1

<div class="post-metadata">

### Author: ![mincheolseong](https://sea2.discourse-cdn.com/flex020/user_avatar/discuss.ray.io/mincheolseong/32/1964_2.png) [@mincheolseong](https://discuss.ray.io/u/mincheolseong)
#### Post date: [January 10, 2022, 10:53am UTC](https://discuss.ray.io/t/how-to-import-actor-that-contains-inherited-class-from-other-module/4637/1 "2022-01-10T10:53:15Z")

</div>

### System model

- Python : 3.8.8
- Ray : 1.9.1
- IDE : Jupyter Notebook
- OS : Windows 10, 64bit

I am currently trying to start an actor that contains inherited class.  
My problem situation can be divided into three categories.

#### First of all, there is an inheritance class in one file.

It works well!

```auto
#main.ipynb
import ray

ray.init()

class para(object):
    def __init__ (self):
        self.para = 1
        
@ray.remote
class Person(para):
    def __init__ (self):
        super(). __init__ ()
    
    def heritage(self):
        return self.para 
    
people = Person.remote()
ray.get(people.heritage.remote())    

```

#### Second, When importing a class without an inherited class from another file,

It works well!

```auto
#a.ipynb
import ray
import numpy as np

@ray.remote
class Person(object):
    def __init__ (self):
        self.name = np.random.choice(['Jon', 'Suasan', 'Frank', 'Anne', 'Ashley', 'Bill'])
    
    def say_hello(self):
        return f"Hi, I'm {self.name}"

```

```auto
#main.ipynb
import import_ipynb
import ray
from a import Person

ray.init()
people = Person.remote()
ray.get(people.say_hello.remote())

```

#### Finally, An error occurs when importing a class that contains an inherited class from another file.

```auto
#a.ipynb
import ray
import numpy as np

class para(object):
    def __init__ (self):
        self.para = 1

@ray.remote
class Person(para):
    def __init__ (self):
        super(). __init__ ()
    
    def heritage(self):
        return self.para 

```

```auto
#main.ipynb
import import_ipynb
import ray
from a import Person

ray.init()
people = Person.remote()
ray.get(people.heritage.remote())

```

Below is the error message.

```auto
 pid=34368) 2022-01-10 19:45:06,467	ERROR worker.py:431 -- Exception raised in creation task: The actor died because of an error raised in its creation task, ray::Person. __init__ () (pid=34368, ip=127.0.0.1)
 pid=34368) File "python\ray\_raylet.pyx", line 625, in ray._raylet.execute_task
 pid=34368) File "python\ray\_raylet.pyx", line 629, in ray._raylet.execute_task
 pid=34368) File "python\ray\_raylet.pyx", line 578, in ray._raylet.execute_task.function_executor
 pid=34368) File "C:\Users\ksshin\anaconda3\lib\site-packages\ray\_private\function_manager.py", line 609, in actor_method_executor
 pid=34368) return method(__ray_actor, *args, **kwargs)
 pid=34368) File "C:\Users\ksshin\anaconda3\lib\site-packages\ray\_private\function_manager.py", line 512, in temporary_actor_method
 pid=34368) raise RuntimeError(
 pid=34368) RuntimeError: The actor with name Person failed to import on the worker. This may be because needed library dependencies are not installed in the worker environment:
 pid=34368) aryActor
 pid=34368) ray::Person. __init__ () (pid=34368, ip=127.0.0.1)
 pid=34368) File "C:\Users\ksshin\anaconda3\lib\site-packages\ray\_private\function_manager.py", line 564, in _load_actor_class_from_gcs
 pid=34368) actor_class = pickle.loads(pickled_class)
 pid=34368) ModuleNotFoundError: No module named 'a'
---------------------------------------------------------------------------
RayActorError Traceback (most recent call last)
<ipython-input-2-91fa4fbb45a9> in <module>
      1 people = Person.remote()
----> 2 ray.get(people.heritage.remote())

~\anaconda3\lib\site-packages\ray\_private\client_mode_hook.py in wrapper(*args, **kwargs)
    103 if func. __name__!= "init" or is_client_mode_enabled_by_default:
    104 return getattr(ray, func. __name__ )(*args, **kwargs)
--> 105 return func(*args, **kwargs)
    106 
    107 return wrapper

~\anaconda3\lib\site-packages\ray\worker.py in get(object_refs, timeout)
   1713 raise value.as_instanceof_cause()
   1714 else:
-> 1715 raise value
   1716 
   1717 if is_individual_id:

RayActorError: The actor died because of an error raised in its creation task, ray::Person. __init__ () (pid=34368, ip=127.0.0.1)
  File "python\ray\_raylet.pyx", line 625, in ray._raylet.execute_task
  File "python\ray\_raylet.pyx", line 629, in ray._raylet.execute_task
  File "python\ray\_raylet.pyx", line 578, in ray._raylet.execute_task.function_executor
  File "C:\Users\ksshin\anaconda3\lib\site-packages\ray\_private\function_manager.py", line 609, in actor_method_executor
    return method(__ray_actor, *args, **kwargs)
  File "C:\Users\ksshin\anaconda3\lib\site-packages\ray\_private\function_manager.py", line 512, in temporary_actor_method
    raise RuntimeError(
RuntimeError: The actor with name Person failed to import on the worker. This may be because needed library dependencies are not installed in the worker environment:

ray::Person. __init__ () (pid=34368, ip=127.0.0.1)
  File "C:\Users\ksshin\anaconda3\lib\site-packages\ray\_private\function_manager.py", line 564, in _load_actor_class_from_gcs
    actor_class = pickle.loads(pickled_class)
ModuleNotFoundError: No module named 'a'

```

I guess there is an error in the process of importing the module, and I searched as much as possible about the ray issue, but could not find a solution.  
I would really appreciate it if you could tell me how to solve it.

---

<div class="post-metadata">

### Author: ![Clark\_Zinzow](https://sea2.discourse-cdn.com/flex020/user_avatar/discuss.ray.io/clark_zinzow/32/445_2.png) [@Clark\_Zinzow](https://discuss.ray.io/u/Clark_Zinzow)
#### Post date: [January 10, 2022, 7:55pm UTC](https://discuss.ray.io/t/how-to-import-actor-that-contains-inherited-class-from-other-module/4637/2 "2022-01-10T19:55:12Z")

</div>

Hi @mincheolseong, thanks for the very detailed issue/reproduction! When running the final snippet, with the `a.ipynb` saved in an `a.py` module and running `main.ipynb` in an IPython notebook, it works for me:

```auto
In [1]: import ray
   ...: from a import Person
   ...:
   ...: ray.init()
   ...: people = Person.remote()
   ...: ray.get(people.heritage.remote())

2022-01-10 19:50:45,244 INFO services.py:1384 -- View the Ray dashboard at http://127.0.0.1:8265
Out[1]: 1

```

This is with Ray 1.9.1, Python 3.7.10, and on Ubuntu, so there’s a chance this is a Windows-specific issue.

---

<div class="post-metadata">

### Author: ![mincheolseong](https://sea2.discourse-cdn.com/flex020/user_avatar/discuss.ray.io/mincheolseong/32/1964_2.png) [@mincheolseong](https://discuss.ray.io/u/mincheolseong)
#### Post date: [January 11, 2022, 9:20am UTC](https://discuss.ray.io/t/how-to-import-actor-that-contains-inherited-class-from-other-module/4637/3 "2022-01-11T09:20:58Z")

</div>

Thanks for your kind reply.  
As you mentioned, I found a problem with importing .ipynb and it works fine with .py.  
I hope that one day I will be able to use ray comfortably with Jupyter notebooks.