code: def instances(cls, parent=None):
          
          if parent is None:
              parent = projexui.topWindow()
          return parent.findChildren(cls)
docs: Returns all the instances that exist for a given parent.  If
          no parent exists, then a blank list will be returned.
          
          :param      parent | <QtGui.QWidget>
          
          :return     [<XView>, ..]