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Better dates and times in Python — timezone-aware by default, human-friendly API, and natural language parsing.
pytest: simple powerful testing with Python
| Metric | arrow | pytest |
|---|---|---|
| Ecosystem | Python | Python |
| Difficulty | Beginner | Beginner |
| Weekly downloads | 2.5M↑ | 0 |
| Latest version | v1.3.0 | v9.0.2 |
| Recipes | 1 | 1 |
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Any application dealing with dates across timezones, relative time displays ('posted 2 days ago'), date parsing from strings, date range iteration, or when you want less boilerplate than stdlib datetime.
Use pytest for any Python project with tests. It's the de facto standard — most libraries, frameworks, and CI pipelines assume pytest. Its plugin ecosystem covers everything from coverage (pytest-cov) to async tests (pytest-asyncio) to parameterisation.
High-frequency numerical date computations (use numpy datetime64 or pandas Timestamp which are faster). Arrow adds overhead per operation.
For extremely simple one-off scripts where adding a dependency feels heavy, unittest is built into Python. For property-based testing, add Hypothesis on top of pytest rather than replacing it.
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pytest