Cell content change

def setData(self, index, value, role=Qt.EditRole):
        """Cell content change"""
        if not index.isValid():
            return False
        if index.column() < 3:
            return False
        value = display_to_value(value, self.get_value(index),
                                 ignore_errors=True)
        self.set_value(index, value)
        self.dataChanged.emit(index, index)
        return True