RequirementsGen

Auto-generates requirements.txt from Python project imports. Scans all .py files, extracts imports, filters out stdlib (comprehensive list for Python 3.8-3.13). Smart package name resolution — knows PIL means Pillow, cv2 means opencv-python, yaml means PyYAML (50+ mappings). Detects installed versions for pinning. Separates dev dependencies (pytest, black, mypy) from production. Outputs requirements.txt and dev-requirements.txt. Shows which files use each import. JSON export. Zero dependencies — single Python file.