title: changing cell background color in qt
body: <p>i'm new to pyqt , and i'm still facing some newbie problems :D<br>
  i have a QTableWidget that is item delegated on a QChoice control ( hope i said it right ) 
  i need to have the cell  background color changes whenever a user change the choice control selection 
  <br>
  briefly: how to change a cell background color in a table widget ??
  <br>
  i use pyqt4 and python 2.6
  <br>
  thanx in advance </p>