code: def initialize_api(flask_app):
      
      if not flask_restplus:
          return
  
      api = flask_restplus.Api(version="1.0", title="My Example API")
      api.add_resource(HelloWorld, "/hello")
  
      blueprint = flask.Blueprint("api", __name__, url_prefix="/api")
      api.init_app(blueprint)
      flask_app.register_blueprint(blueprint)
docs: Initialize an API.