explain this code to me: def select_cell(self, cell): if self.selected_cell: self.selected_cell.deselect() self.selected_cell = cell self.selected_cell.select() in python

This is a method within a class which selects a certain cell object and deselects any previously selected object.

First, it checks if an object is already selected by checking if self.selected_cell exists. If it does, it calls the deselect() method on the currently selected cell, which will deselect it.

Then, it sets the selected cell to cell.

Finally, it calls the select() method on the newly selected cell, which will highlight it or mark it as selected.

This code assumes that the cells have select() and deselect() methods that can be used to select and deselect them, respectively. Furthermore, this method depends on the state of the object it's defined within, as it relies on and modifies self.selected_cell.