deal (pypi): **Deal** is a Python library for [design by contract][wiki] (DbC) programming.
Keywords: deal|contracts|pre|post|invariant|decorators|validation|pythonic|functional|contracts-programming|dbc|design-by-contract|flake8|functional-programming|hacktoberfest|interface|linter|mypy|property-based-testing|python|refinement-types|testing|typing