Cannot resolve symbol 'RequestQueue' : <p>I am new to android studio and volley library so please bear with me.</p>

<p>I've added volley library by GitHub and then and added this line to build gradle file: compile 'com.android.support:appcompat-v7:23.0.1'</p>

<p>And now I am trying some tutorials about request and response from api, but for some reason I cannot make an instance of RequestQueue why? 
I am using Android 4.0.3 IceCreamSandwish</p>

<p>Thank you</p>
