How to use the pydruid.db.connect function in pydruid

def _connect(self):
        from pydruid.db import connect
        logger.info('Connecting to Druid database ...')
        self.__druid = connect(self.host, self.port, path='/druid/v2/sql/', scheme='http')
        if self.username or self.password:
            logger.warning(
                'Duct username and password not passed to pydruid connection. '
                'pydruid connection currently does not allow these fields to be passed.'

def get_conn(self):
        """
        Establish a connection to druid broker.
        """
        conn = self.get_connection(self.druid_broker_conn_id)
        druid_broker_conn = connect(
            host=conn.host,
            port=conn.port,
            path=conn.extra_dejson.get('endpoint', '/druid/v2/sql'),
            scheme=conn.extra_dejson.get('schema', 'http'),
            user=conn.login,
            password=conn.password
        )
        self.log.info('Get the connection to druid broker on %s using user %s', conn.host, conn.login)
        return druid_broker_conn

def run_query(self, query, user):
        connection = connect(host=self.configuration['host'],
                             port=self.configuration['port'],
                             path='/druid/v2/sql/',
                             scheme=(self.configuration.get('scheme') or 'http'),
                             user=(self.configuration.get('user') or None),
                             password=(self.configuration.get('password') or None))

        cursor = connection.cursor()

        try:
            cursor.execute(query)
            columns = self.fetch_columns([(i[0], TYPES_MAP.get(i[1], None)) for i in cursor.description])
            rows = [dict(zip((column['name'] for column in columns), row)) for row in cursor]

            data = {'columns': columns, 'rows': rows}
            error = None
            json_data = json_dumps(data)