do not use any of the respective native JS methods to implement your solutions(javascrpt)

lastIndexOf() Without using the native Array.prototype.lastIndexOf" method of JavaScript, compose a function titled "myUnshift" (typo) that will take in an array of elements and returns the index of the last encounter of a target element (if it is found) or -1 if that element does not exist within the input array. Object.keys() Without using the native "Object.keys()" method of JavaScript, compose a function titled "grabkeys that will take in an object and return all of the keys of the key:value pairs of that object. Modify the Object class, appending a static method to the Object class., appending a static method to the Object class. Leverage the for...in loop. Object.values() Without using the native "Object.values()" method of JavaScript, compose a function titled grabValues that will take in an object and return all of the values of the key:value pairs of that object. Modify the Object class, appending a static method to the Object class. Leverage the "for...in loop