python

Type hints in Python declare expected data types for function arguments and returns, enabling static type checking and IDE support. Modern Python uses the typing module and PEP 484 annotations to catch errors before runtime and improve code clarity for production systems.

Asyncio enables concurrent I/O operations using async functions and await expressions. Structure async code by marking coroutines with async def, awaiting async calls, and using asyncio.run() or event loops to execute them—essential for production services handling multiple concurrent requests.

Pytest is a testing framework where you write test functions prefixed with test_, use assert statements for validation, and organize tests in dedicated files. Running pytest discovers and executes all tests, reporting failures clearly—critical for maintaining code quality in production.

PEP 8 is Python's style guide ensuring consistent formatting, naming conventions, and code structure across teams. Adhering to PEP 8 improves readability, reduces bugs, and simplifies maintenance—fundamental for production-grade codebases that multiple developers contribute to.

Pyproject.toml is the modern configuration file for Python packaging, defining project metadata, dependencies, and build system settings. It replaces setup.py and provides a standardized way to distribute and version production Python packages across environments.

Yes, type hints work with async functions by annotating coroutine return types using Awaitable or specifying the resolved type directly. This combination provides full type safety for async production code, catching type errors and improving IDE autocompletion for concurrent operations.