Incorrect typing of iter_chunks in StreamingBody for aiobotocore

[vikigenius]

Describe the bug
A clear and concise description of what the bug is.

To Reproduce
Steps to reproduce the behavior:

1. Install types-aioboto3[essential]
2. Run mypy/pyright on the following code sample

import aioboto3


        async with self.session.client('lambda', config=BotoConfig(read_timeout=5)) as lambda_client:
            response = await lambda_client.invoke(
                FunctionName="SOME_NAME",
                InvocationType='RequestResponse',
                Payload=json.dumps(event)
            )
            payload_str: str = ""
            async for chunk in response["Payload"].iter_chunks():  # This complains
                payload_str += chunk.decode('utf-8')

Actual output

Coroutine[Any, Any, Iterator[bytes]] is not iterable

Expected output
The code actually works. I think the type stubs defined here for iter_chunks is wrong

mypy_boto3_builder/mypy_boto3_builder/stubs_static/aiobotocore/response.pyi

Line 32 in 51f2475

async def iter_chunks(self, chunk_size: int = ...) -> Iterator[bytes]: ...

I think it should return AsyncIterator[bytes] or AsyncGenerator[bytes, None]

Considering this is how the implementation looks

    async def iter_chunks(self, chunk_size=_DEFAULT_CHUNK_SIZE):
        """Return an iterator to yield chunks of chunk_size bytes from the raw
        stream.
        """
        while True:
            current_chunk = await self.read(chunk_size)
            if current_chunk == b"":
                break
            yield current_chunk

https:/aio-libs/aiobotocore/blob/5a17c06a0f46faa1de0ee5cf68b3ea4a235ad5d2/aiobotocore/response.py#L107

[vemel]

Hello! Thank you for the report.

yes, type annotations for StreamingBody.iter_chunks was incorrect. Actually, today I learned something new about typing of async functions with yield statement.

from typing import AsyncIterator

async def my_iterator():
   yield 1
   yield 2
   yield 3

# proper type annotation, notice that the function is not async, because it is NOT a Coroutine
def my_iterator() -> AsyncIterator[int]: ...

So, actual fix: b5ef523#diff-b624a491f4f7431852b61983c966c273705c5fdc397811a0710dd3ed0595a8d6R31

I fixed type annotations for StreamingBody.iter_chunks and StreamingBody.iter_lines in the latest mypy_boto3_builder release. Also, I released packages with the fix incuded:

• types-aiobotocore 2.13.1.post1
• types-aiobotocore-lite 2.13.1.post1
• types-aiobotocore 2.13.2.post1
• types-aiobotocore-lite 2.13.2.post1

Please update and let me know if it works as it should.

[vikigenius]

This seems to have fixed the issue. Thanks for resolving this so quickly.