httpx

Python async HTTP clients provide both synchronous and asynchronous APIs to execute network requests. This allows you to run concurrent API calls with HTTP/2 support and configurable connection pooling across modern applications.

The best way to handle API authentication and custom headers is using a configurable HTTP client. You define base_url, headers, and auth options once, and the client applies them consistently across all outgoing requests.

Streaming large HTTP responses works by processing data chunks incrementally rather than loading the entire payload into memory. This ensures robust data transfer and prevents memory exhaustion during heavy network operations in Python async applications.

You need a Python HTTP client that explicitly supports HTTP/2 and proxy configuration to utilize these features. A unified client allows you to configure proxies, timeouts, and redirects while maintaining connections over the HTTP/2 protocol.

Synchronous API requests block the Python application event loop because they wait for network responses sequentially. Using a unified sync/async HTTP client lets you switch to an asynchronous API to prevent blocking during network operations.