Essentials OpenAPI provides classes and utilities to generate OpenAPI
Documentation in both version 3 and version 2 formats. It supports
output in JSON and YAML formats for API documentation.

Key features:
* Generate OpenAPI 3.x and 2.x documentation
* Support for JSON and YAML output formats
* Automatic schema generation from Python types
* Integration with web frameworks
* Extensible documentation system
* Template-based documentation generation
* Command-line interface for documentation generation

This library is particularly useful for web APIs that need to generate
comprehensive API documentation automatically from code annotations.