Python Libraries¶
Practical guides for key Python libraries: core API, patterns, and production best practices.
Section Map¶
| Library | Focus |
|---|---|
| Requests / HTTP | HTTP client: methods, sessions, auth, retries, streaming, best practices |
| Pytest | Testing: fixtures, parametrize, markers, mocking, coverage, plugins, CI patterns |
| Playwright | Browser & API testing: locators, POM, assertions, network mocking, CI |
| HTTPX | Async HTTP client: sync/async, HTTP/2, streaming, concurrency, FastAPI testing |
| Pydantic | Data validation: models, fields, validators, serialization, settings, TypeAdapter |
| SQLAlchemy | ORM & SQL toolkit: models, relationships, sessions, async, Alembic, performance |
| FastAPI | Async web framework: routing, DI, auth, DB integration, testing, production, ASGI stack |
| Jinja | Templates: syntax, filters, inheritance, macros, autoescape, StrictUndefined, sandbox/SSTI, reports, LLM prompts, testing |
| uv | Python project manager: deps, scripts, tools, workspaces, Docker, build & publish |
| LangChain | LLM framework: models, LCEL chains, RAG, agents, tools, memory, LangGraph, LangSmith |
| LangGraph | Stateful agent graphs: state and reducers, Command/Send, checkpointers, Store, interrupts, streaming, multi-agent, testing, LangGraph Server |
| Guardrails AI | LLM guards: validators, on-fail actions, structured output, PII/jailbreak/toxicity checks, server, testing |
| LiteLLM | LLM gateway: one API for 100+ providers, tools, structured output, router, fallbacks, proxy, cost tracking |
| OpenTelemetry | Observability: traces, metrics, logs, auto-instrumentation, Collector, testing with spans |
| Code Quality | Linters, formatters, type checkers, pre-commit hooks, test coverage, mutation testing |