import { Transaction } from '../../types';
/**
 *
 * @param value
 * @returns
 */
export declare function isTransactionObject(value: string | Transaction): value is Transaction;
/**
 *
 * @param address
 * @returns
 */
export declare function isSystemContract(address: string): boolean;
/**
 *
 * @param {string} address
 * @returns {Promise<boolean>}
 */
export declare function checkIsContract(address: string): Promise<boolean>;
/**
 *
 * @param {string} address
 * @returns {Promise<string>}
 */
export declare function getContractBytecode(address: string): Promise<string>;