title: can sprite group in pygame contain subgroups containing sprites apart from the normal sprites ?
body: <p>I am new to pygame and I was wondering if the following was possible. </p>
  
  <p>Say I have 2 Spritegroups called Sprites and Sprites1 each having a set of different non overlapping sprites in them. Is it possible to do something like Sprites.add(Sprites1) ? </p>