>>> async def some():
...    yield 1
... 
>>> some()
<async_generator object some at 0x10559d300>
>>> some().ag_suspended
False
>>> some().ag_suspended = True
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
AttributeError: attribute 'ag_suspended' of 'async_generator' objects is not writable