How to use the flasgger.utils.extract_definitions function in flasgger

# pop, assert single element
                    update_dict, = update_dict
                definitions.update(update_dict)
                defs = []  # swag.get('definitions', [])
                defs += extract_definitions(
                    defs, endpoint=rule.endpoint, verb=verb,
                    prefix_ids=prefix_ids
                )

                params = swag.get('parameters', [])
                if verb in swag.keys():
                    verb_swag = swag.get(verb)
                    if len(params) == 0 and verb.lower() in http_methods:
                        params = verb_swag.get('parameters', [])

                defs += extract_definitions(params,
                                            endpoint=rule.endpoint,
                                            verb=verb,
                                            prefix_ids=prefix_ids)

                request_body = swag.get('requestBody')
                if request_body:
                    content = request_body.get("content", {})
                    extract_definitions(
                        list(content.values()),
                        endpoint=rule.endpoint,
                        verb=verb,
                        prefix_ids=prefix_ids
                    )

                callbacks = swag.get("callbacks", {})
                if callbacks:

extract_definitions(
                        list(callbacks.values()),
                        endpoint=rule.endpoint,
                        verb=verb,
                        prefix_ids=prefix_ids
                    )

                responses = None
                if 'responses' in swag:
                    responses = swag.get('responses', {})
                    responses = {
                        str(key): value
                        for key, value in responses.items()
                    }
                    if responses is not None:
                        defs = defs + extract_definitions(
                            responses.values(),
                            endpoint=rule.endpoint,
                            verb=verb,
                            prefix_ids=prefix_ids
                        )
                    for definition in defs:
                        if 'id' not in definition:
                            definitions.update(definition)
                            continue
                        def_id = definition.pop('id')
                        if def_id is not None:
                            definitions[def_id].update(definition)

                operation = {}
                if swag.get('summary'):
                    operation['summary'] = swag.get('summary')

specs = get_specs(
            self.get_url_mappings(spec.get('rule_filter')), ignore_verbs,
            optional_fields, self.sanitizer,
            doc_dir=self.config.get('doc_dir'))

        http_methods = ['get', 'post', 'put', 'delete']
        for rule, verbs in specs:
            operations = dict()
            for verb, swag in verbs:
                update_dict = swag.get('definitions', {})
                if type(update_dict) == list and type(update_dict[0]) == dict:
                    # pop, assert single element
                    update_dict, = update_dict
                definitions.update(update_dict)
                defs = []  # swag.get('definitions', [])
                defs += extract_definitions(
                    defs, endpoint=rule.endpoint, verb=verb,
                    prefix_ids=prefix_ids
                )

                params = swag.get('parameters', [])
                if verb in swag.keys():
                    verb_swag = swag.get(verb)
                    if len(params) == 0 and verb.lower() in http_methods:
                        params = verb_swag.get('parameters', [])

                defs += extract_definitions(params,
                                            endpoint=rule.endpoint,
                                            verb=verb,
                                            prefix_ids=prefix_ids)

                request_body = swag.get('requestBody')

params = swag.get('parameters', [])
                if verb in swag.keys():
                    verb_swag = swag.get(verb)
                    if len(params) == 0 and verb.lower() in http_methods:
                        params = verb_swag.get('parameters', [])

                defs += extract_definitions(params,
                                            endpoint=rule.endpoint,
                                            verb=verb,
                                            prefix_ids=prefix_ids)

                request_body = swag.get('requestBody')
                if request_body:
                    content = request_body.get("content", {})
                    extract_definitions(
                        list(content.values()),
                        endpoint=rule.endpoint,
                        verb=verb,
                        prefix_ids=prefix_ids
                    )

                callbacks = swag.get("callbacks", {})
                if callbacks:
                    callbacks = {
                        str(key): value
                        for key, value in callbacks.items()
                    }
                    extract_definitions(
                        list(callbacks.values()),
                        endpoint=rule.endpoint,
                        verb=verb,