PythonAsyncioJumpStart/src/lesson04_async_iterator.py at main · SuperFastPython/PythonAsyncioJumpStart · GitHub

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# SuperFastPython.com
# example of an async iterator with async for loop
importasyncio

# define an asynchronous iterator
classAsyncIterator():
# constructor, define some state
def__init__(self):
self.counter=0

# create an instance of the iterator
def__aiter__(self):
returnself

# return the next awaitable
asyncdef__anext__(self):
# check for no further items
ifself.counter>=10:
raiseStopAsyncIteration
# increment the counter
self.counter+=1
# simulate work
awaitasyncio.sleep(1)
# return the counter value
returnself.counter

# main coroutine
asyncdefmain():
# loop over async iterator with async for loop
asyncforiteminAsyncIterator():
print(item)

# execute the asyncio program
asyncio.run(main())