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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 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
            await yield_(current_chunk)