'When a tab is deleted, all other tabs must be renamed to reacomodate
the numbers'

def reorder_tab_names(self):

    number_of_tabs = self.notebook.get_n_pages()
    for n in range(number_of_tabs):
        tab = self.notebook.get_nth_page(n)
        self.notebook.set_tab_label_text(tab, str((n + 1)))
    self.tab_number = (number_of_tabs - 1)
