Testing & Data Quality Production testing strategies with pytest, data validation, and quality frameworks. Quick Start Core Concepts 1. Data Validation with Pydantic 2. Great Expectations 3. Integration Testing 4. Mocking External Services Tools & Technologies | Tool | Purpose | Version (2025) | |------|---------|----------------| | pytest | Testing framework | 8.0+ | | Great Expectations | Data validation | 0.18+ | | Pydantic | Data validation | 2.5+ | | pytest-cov | Code coverage | 4.1+ | | testcontainers | Integration testing | 3.7+ | | responses | HTTP mocking | 0.25+ | | hypothesis | Pro…