Python async/await — Waiting Without Blocking

import asyncio import httpx async def fetch(client: httpx.AsyncClient, url: str) -> dict: response = await client.get(url, timeout=10) response.raise_for_status() return response.json() async def main() -> None: urls = [ "https://api.github.com/users/anthropic", "https://api.github.com/users/openai", "https://api.github.com/users/vercel", ] async with httpx.AsyncClient() as client: results = await asyncio.gather(*(fetch(client, u) for u in urls)) for data in results: print(data["login"], "-", data.get("bio", "")) asyncio.run(main())

import asyncio from anthropic import AsyncAnthropic client = AsyncAnthropic() semaphore = asyncio.Semaphore(5) # max 5 concurrent requests async def summarize(text: str) -> str: async with semaphore: response = await client.messages.create( model="claude-opus-4-7", max_tokens=200, messages=[{"role": "user", "content": f"One sentence summary:\n{text}"}], ) return response.content[0].text async def main(): articles = ["text 1", "text 2", "text 20"] summaries = await asyncio.gather(*(summarize(a) for a in articles)) for s in summaries: print(s) asyncio.run(main())

results = await asyncio.gather( *(fetch(client, u) for u in urls), return_exceptions=True, # don't fail-fast ) for url, result in zip(urls, results): if isinstance(result, Exception): print(f"Failed {url}: {result}") else: print(f"OK {url}")