Nodejs Utililty Methods Class Inherit

Function.prototype.inheritsFrom = function( parentClassOrObject ){ 
  this.prototype.addPrototype( parentClassOrObject );
  if ( parentClassOrObject.constructor == Function ) 
    this.prototype.addPrototype( new parentClassOrObject );
    this.prototype.constructor = this;
    this.prototype.__parent__ = parentClassOrObject.prototype;
  else 
...

Object.prototype.inherits = function inherits(parent) {
    if (typeof Object.create !== 'function') {
        Object.create = function (o) {
            function F() {}
            F.prototype = o;
            return new F();
        };
    this.prototype = Object.create(parent.prototype);
...

Object.deepExtend = function (destination, source) {
    for (var property in source) {
        if (source[property] && source[property].constructor &&
         source[property].constructor === Object) {
            destination[property] = destination[property] || {};
            arguments.callee(destination[property], source[property]);
        } else {
            destination[property] = source[property];
    return destination;
};