/**
 * Copies properties from one or more source objects to a target object.
 *
 * The extend function takes an object target as its first argument, and any
 * number of additional objects as subsequent arguments. It copies all properties
 * from each source object to the target object, and returns the modified target object.
 *
 * Only copies properties that are directly on the source object (not inherited).
 *
 * @param {Object} target - The target object to copy properties to.
 * @param {...Object} sources - One or more source objects to copy properties from.
 * @returns {Object} The modified target object.
 */
export function _extend(target: any, ...args: any[]): any;
export default _extend;