How to use the webtech.database.merge_databases function in webtech

self.db = database.merge_databases(self.db, json.load(f))

        # Output text only
        self.output_format = Format['text']

        # Default user agent
        self.USER_AGENT = default_user_agent()

        if options is None:
            return
        self.scrape_url = options.get('scrape')

        if options.get('database_file'):
            try:
                with open(options.get('database_file')) as f:
                    self.db = database.merge_databases(self.db, json.load(f))
            except (FileNotFoundException, ValueError) as e:
                print(e)
                exit(-1)

        self.urls = options.get('urls') or []

        if options.get('urls_file'):
            try:
                with open(options.get('urls_file')) as f:
                    self.urls = [line.rstrip() for line in f]
            except FileNotFoundException as e:
                print(e)
                exit(-1)

        if options.get('user_agent'):
            self.USER_AGENT = options.get('user_agent')

def __init__(self, options=None):
        if not BURP:
            update = False if options is None else options.get('update_db', False)
            database.update_database(force=update)

        with open(database.WAPPALYZER_DATABASE_FILE) as f:
            self.db = json.load(f)
        with open(database.DATABASE_FILE) as f:
            self.db = database.merge_databases(self.db, json.load(f))

        # Output text only
        self.output_format = Format['text']

        # Default user agent
        self.USER_AGENT = default_user_agent()

        if options is None:
            return

        if options.get('database_file'):
            try:
                with open(options.get('database_file')) as f:
                    self.db = database.merge_databases(self.db, json.load(f))
            except (FileNotFoundException, ValueError) as e:
                print(e)

def __init__(self, options=None):
        if not BURP:
            update = False if options is None else options.get('update_db', False)
            database.update_database(force=update)

        with open(database.WAPPALYZER_DATABASE_FILE) as f:
            self.db = json.load(f)
        with open(database.DATABASE_FILE) as f:
            self.db = database.merge_databases(self.db, json.load(f))

        # Output text only
        self.output_format = Format['text']

        # Default user agent
        self.USER_AGENT = default_user_agent()

        if options is None:
            return
        self.scrape_url = options.get('scrape')

        if options.get('database_file'):
            try:
                with open(options.get('database_file')) as f:
                    self.db = database.merge_databases(self.db, json.load(f))
            except (FileNotFoundException, ValueError) as e: