What is an async generator?

Question

Accepted Answer

**Async generator** combines `async def` and `yield`. Produces values asynchronously.

```python
import asyncio

async def async_range(start, stop):
    current = start
    while current < stop:
        await asyncio.sleep(0.1)  # Async operation
        yield current
        current += 1

async def main():
    async for num in async_range(0, 5):
        print(num)  # 0, 1, 2, 3, 4

asyncio.run(main())
```

**Async generator expression:**
```python
async def fetch(url):
    await asyncio.sleep(1)
    return url

# Async generator expression
async_gen = (await fetch(url) for url in urls)

# With comprehension
results = [await fetch(url) async for url in urls]
```

**Use cases:**
- Streaming API responses.
- Database cursors.
- Real-time data processing.

Python: What is an async generator?