More clarification on zap-api-scan.py

Hello, I’d like to clarify the purpose of the zap-api-scan.py script. Is it included with ZAP, or do we have to create this file ourselves? I’m not entirely clear on this aspect. Here’s the Docker command for reference:
docker run -v$(pwd):/zap/wrk/:rw -t owasp/zap2docker-weekly zap-api-scan.py -t $applicationURL :$PORT/v3/api-docs -f openapi -r zap_report.html