Sets whether or not the inputed flag is associated with this item.
        
        :param      flag  | <QtCore.Qt.ItemFlags>
                    state | <bool>

def setFlag(self, flag, state=True):
        """
        Sets whether or not the inputed flag is associated with this item.
        
        :param      flag  | <QtCore.Qt.ItemFlags>
                    state | <bool>
        """
        if state:
            self.setFlags(self.flags() | flag)
        else:
            self.setFlags(self.flags() & ~flag)