Sets the default item foreground brush.
        
        :param      brush | <QtGui.QBrush> || None

def setForeground(self, column, brush):
        """
        Sets the default item foreground brush.
        
        :param      brush | <QtGui.QBrush> || None
        """
        if brush:
            self._foreground[column] = QtGui.QBrush(brush)
        elif column in self._background:
            self._foreground.pop(column)