def on_value_change(self, picker, old, new):
        """ Set the checked property based on the checked state
        of all the children
            
        """
        d = self.declaration
        with self.widget.setValue.suppressed():
            d.value = new
def on_value_change ( self , picker , old , new ) : d = self . declaration with self . widget . setValue . suppressed ( ) : d . value = new
Set the checked property based on the checked state
        of all the children