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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def set_info_mapper_model(self, mapper, model):
 """Set the model for the info mapper :param mapper: the mapper to update :type mapper: QtGui.QDataWidgetMapper :param model: The model to set :type model: QtGui.QAbstractItemModel | None :returns: None :rtype: None :raises: None """

        # nothing changed. we can return.
        # I noticed that when you set the model the very first time to None
        # it printed a message:
        # QObject::connect: Cannot connect (null)::dataChanged(QModelIndex,QModelIndex) to
        # QDataWidgetMapper::_q_dataChanged(QModelIndex,QModelIndex)
        # QObject::connect: Cannot connect (null)::destroyed() to
        # QDataWidgetMapper::_q_modelDestroyed()
        # I don't know exactly why. But these two lines get rid of the message and outcome is the same
        if not mapper.model() and not model:
            return

        mapper.setModel(model)
        if mapper is self.asset_info_mapper:
            if model is None:
                self.asset_path_le.setText("")
                self.asset_created_by_le.setText("")
                self.asset_created_dte.findChild(QtGui.QLineEdit).setText('')
                self.asset_updated_dte.findChild(QtGui.QLineEdit).setText('')
            else:
                mapper.addMapping(self.asset_path_le, 2)
                mapper.addMapping(self.asset_created_by_le, 3)
                mapper.addMapping(self.asset_created_dte, 4)
                mapper.addMapping(self.asset_updated_dte, 5)
        else:
            if model is None:
                self.shot_path_le.setText("")
                self.shot_created_by_le.setText("")
                self.shot_created_dte.findChild(QtGui.QLineEdit).setText('')
                self.shot_updated_dte.findChild(QtGui.QLineEdit).setText('')
            else:
                mapper.addMapping(self.shot_path_le, 2)
                mapper.addMapping(self.shot_created_by_le, 3)
                mapper.addMapping(self.shot_created_dte, 4)
                mapper.addMapping(self.shot_updated_dte, 5)