diff --git a/default.py b/default.py
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+++ b/default.py
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+# The Mac OS Updater
+## Install macOS updates from the TUI. 
+
+import os; import time as clock
+
+
+## app information
+class app: 
+    title = "The Mac OS Updater"
+    description = "Install macOS updates from the TUI."
+    version = 22.0616 ### YY.MMDD
+
+## localization
+class texts: 
+    current_language = "en"
+    
+    class screens: 
+        class titles: 
+            s_2_0 = 'Download macOS'
+            s_2_1 = 'Advanced Options'
+            s_2_2 = 'Beta Update Branch Removal'
+            s_2_2_1 = 'Disabling Beta Branch Search…'
+        
+        class messages: 
+            s_2_1 = 'Select the beta update branch to be included.'
+            s_2_2 = 'Do you want to remove the beta update branch when looking for updates? '
+            s_2_3 = 'Please read and agree to the lisence before to include the public beta update branch.'
+            s_2_4 = 'Please read and agree to the lisence before to include the developer beta update branch.'
+    
+    class menus: 
+        main = ['quit', 'refresh', 'install updates', 'download macOS', 'help']
+        s_2_0 = ['⬅︎' , 'refresh', 'advanced', 'download: Type an OS version number to download it.']
+        s_2_1 = ['⬅︎' , '🚫', 'beta release', 'developer release']
+        s_2_2 = ['⬅︎' , 'revert']
+        s_2_3 = ['⬅︎' , 'agree']
+        s_2_4 = ['⬅︎' , 'agree']
+    
+    class status: 
+        class checkCompatibility:
+            checking = 'Checking compatibility…'
+            done = ''
+    
+    class errors: 
+        class compatibility: 
+            incompatibility = "There is no use running this outside macOS."
+            noSoftwareUpdater = "There is no CLI software updater. \nAre you using an old version of macOS?"
+        
+        class quit: 
+            terminationPrompt = "The program refuses to proceed, so it will be closed. \nTo continue, click enter or quit the program yourself."
+        
+        class default: 
+            syntaxerr = "There is a spelling mistake!"
+            typeerr = "Too bad, something couldn't be converted."
+            attributeerr = "Something was not linked in properly. "
+
+        class screens: 
+            s_2_2_1: 'Sorry. You are still stuck with the beta branch search enabled. \nPress ^c to go back, and come back to this page to try again.'
+try: 
+    ## on Terminal outputs
+    ### text formatting
+    class formatting:
+        clear = '\033[0m'
+        class color: 
+            purple = '\033[95m'
+            cyan = '\033[96m'
+            cyan_dark = '\033[36m'
+            blue = '\033[94m'
+            green = '\033[92m'
+            yellow = '\033[93m'
+            red = '\033[91m'
+        class font:
+            bold = '\033[1m'
+            underline = '\033[4m'
+
+    ### screen functions
+    def cls(times = 1): #### to clear screen
+        times = int(abs(times));
+        for _ in range(times):
+            try: 
+                ipy_str = str(type(get_ipython()))
+                if 'zmqshell' in ipy_str: from IPython.display import clear_output as clear; clear()
+                elif 'terminal' in ipy_str: clear
+            except NameError: ##### The user is running directly from the terminal, which is expected.  
+                import os; return(os.system('clear'))
+
+    class info: ### screen messages
+        def status(message): print(formatting.font.bold + 'ℹ️\t' + formatting.clear + message)
+        def err(message): print(formatting.font.bold + formatting.color.red + '❌\t' + formatting.clear + formatting.clear + message)
+        def warning(message): print(formatting.font.bold + formatting.color.yellow + '⚠️\t' + formatting.clear + formatting.clear + message)
+        def success(message): print(formatting.font.bold + formatting.color.green + '✅\t' + formatting.clear + formatting.clear + message)
+        
+        ### terminate with fail function
+    def fail(message = '', displayAppInformation = True, critical = True): 
+        import time;
+
+        if critical: 
+            try: 
+                if displayAppInformation: operations.display_title_screen(); print('\n')
+                info.err(message); input('\n\n' + texts.errors.quit.terminationPrompt); raise KeyboardInterrupt
+            except KeyboardInterrupt: cls(); exit()
+        else: print(message)
+        time.sleep(1);
+
+    class user: ## user data
+        class navigation: ### TLI data
+            screen = 0 
+            response = ''
+            
+            class window: 
+                try: 
+                    width = int((os.get_terminal_size()).columns)
+                    lines = int((os.get_terminal_size()).lines)
+                except OSError: 
+                    width = False
+                    lines = False
+        
+        class compatibility: ### for operations.check_compatibility()
+            isRunningMacOS = (os.name =='posix' and not(os.system('cd /Applications')) and not(os.system('cd /Library')) and not(os.system('cd /System/Library')))
+            hasCLIUpdaterInstalled = not(os.system('softwareupdate --help  >/dev/null 2>&1')) #### Check if softwareupdate command is there. 
+        
+        class shell: 
+            try: #### determine Python type, if running in terminal, ipython, or jupyter
+                ipy_str = str(type(get_ipython()))
+                if 'zmqshell' in ipy_str: pythonType = 'jupyter'
+                elif 'terminal' in ipy_str: pythonType = 'ipython'
+            except:
+                pythonType = 'terminal'
+    
+    class operations: ## all operations
+        def display_title_screen(message = ''): ### display title screen and optional message
+            screenManager.menu.titleBar(app.title); print (app.description + '\nV' + str(app.version)) #### display app information
+            message = str(message).strip()
+            if message != '': print(message) #### display message
+
+        def check_compatibility(): ### compatibility check
+            cls()
+            operations.display_title_screen(texts.status.checkCompatibility.checking)
+
+            import os
+            if user.compatibility.isRunningMacOS: 
+                if user.compatibility.hasCLIUpdaterInstalled: 
+                    return True
+                else: 
+                    fail(texts.errors.compatibility.noSoftwareUpdater); return False
+            else: 
+                fail(texts.errors.compatibility.noSoftwareUpdater); return False
+        
+        class software: 
+            def check_updates(): 
+                import os
+                return(os.system('softwareupdate -l'))
+            def check_OS_installers(): 
+                import os
+                return(os.system('softwareupdate --list-full-installers'))
+            
+            class installer_branch: 
+                def none(): 
+                    import os; return(os.system('sudo /System/Library/PrivateFrameworks/Seeding.framework/Versions/A/Resources/seedutil unenroll'))
+                
+                def publicBeta(): 
+                    import os; return(os.system('sudo /System/Library/PrivateFrameworks/Seeding.framework/Versions/A/Resources/seedutil enroll PublicSeed'))
+                
+                def privateBeta(): 
+                    import os; return(os.system('sudo /System/Library/PrivateFrameworks/Seeding.framework/Versions/A/Resources/seedutil enroll DeveloperSeed'))
+        
+    class screenManager: ## TLI
+        
+        class graphical: 
+            def horizontalLine(times = 1):
+                times = int(abs(times))
+                if times == 0: 
+                    times = 1
+                
+                for _ in range(times): 
+                    screenManager.redefineDimensions()
+                    
+                    if user.navigation.window.width != False: 
+                        totalText = ''
+                        for _ in range(user.navigation.window.width): totalText = totalText + '—'
+                        print(totalText)
+                    else: print('')
+        
+        class menu: ### for menus
+            def titleBar(title): 
+                title = title.strip()
+                titleLength = len(title)
+                
+                totalText = ''
+                if user.navigation.window.width != False: 
+                    for _ in range(int(((user.navigation.window.width - titleLength)/2)-1)): totalText = totalText + '—'
+                    totalText = (totalText + ' ')
+                
+                totalText = (totalText + formatting.font.bold + title + formatting.clear)
+                
+                if user.navigation.window.width != False: 
+                    totalText = (totalText + ' ')
+                    for _ in range(int(((user.navigation.window.width - titleLength)/2)-1)): totalText = totalText + '—'
+                
+                print(totalText); return(totalText)
+            
+            def topMenu(menuShortcut, menuList, displayHorizontalLineBelow = True): #### bottom menu
+                entryNumber = 0; displayText = '|'
+                for menuItem in menuList: 
+                    entryNumber = menuList.index(menuItem)
+                    
+                    if menuShortcut[entryNumber].strip() == '': 
+                        displayText = (displayText + menuItem + '|')
+                    else: 
+                        displayText = (displayText + formatting.font.bold + menuShortcut[entryNumber] + formatting.clear + ' ' + menuItem + '|')
+                print(displayText); 
+                if displayHorizontalLineBelow: screenManager.graphical.horizontalLine()
+            
+            def inputMenu(menuShortcut, menuList, backSupported = True, passNumbers = False, passAnything = False): #### input
+                while True: 
+                    screenManager.graphical.horizontalLine(); 
+                    try: 
+                        response = input()
+                        response = response.strip()
+                    except KeyboardInterrupt: ##### User cancelled. 
+                        if backSupported: return -1; 
+                        else: print("", end="\r") ##### Loop again. 
+                    else: 
+                        if response in menuShortcut or response in menuList or passAnything: 
+                            return(response)
+                        elif passNumbers: 
+                            try: response = float(response)
+                            except: print("", end="\r")
+                            else: return(response)
+                        else: print("", end="\r")
+            
+            def promptMenu(promptTitle, promptDescription, promptOptions, promptShortcuts, canCancel = True, extraInputAllowed = False, numbersAllowed = False): 
+                screenManager.menu.titleBar(promptTitle.strip())
+                
+                print(promptDescription)
+                
+                if user.navigation.window.lines != False: 
+                    for _ in range((user.navigation.window.lines)/4): print('')
+                else: print('\n\n')
+                    
+                screenManager.menu.topMenu(promptShortcuts, promptOptions)
+                
+                user.navigation.response = screenManager.menu.inputMenu(promptShortcuts, promptOptions, canCancel, numbersAllowed, extraInputAllowed)
+                return(user.navigation.response)
+            
+        def redefineDimensions(): 
+            try: user.navigation.window.width = int((os.get_terminal_size()).columns)
+            except OSError: user.navigation.window.width = False
+
+            try: user.navigation.window.lines = int((os.get_terminal_size()).lines)
+            except OSError: user.navigation.window.lines = False
+        
+        def do(): 
+            while user.navigation.screen >= 0: 
+                cls(); screenManager.redefineDimensions()
+
+                if user.navigation.screen < 1: ### when opened
+                    if user.navigation.screen == 0: 
+                        operations.display_title_screen()
+                        clock.sleep(1)
+                        user.navigation.screen = 0.1
+
+                    elif user.navigation.screen == 0.1: 
+                        if operations.check_compatibility(): user.navigation.screen = 1
+
+                elif user.navigation.screen < 2: 
+                    if user.navigation.screen == 1: 
+                        menuShortcut = ['^c', 'r', 'i', 'd', '?']
+                        
+                        screenManager.menu.titleBar(app.title); screenManager.menu.topMenu(menuShortcut, texts.menus.main)
+                        
+                        operations.software.check_updates()
+                        
+                        user.navigation.response = screenManager.menu.inputMenu(menuShortcut, texts.menus.main)
+                        
+                        if user.navigation.response == -1 or user.navigation.response == '^c': 
+                            user.navigation.screen = -1
+                        elif user.navigation.response == 'd': 
+                            user.navigation.screen = 2
+                            
+                elif user.navigation.screen < 3: ### full installer downloader, necessary and recommended to upgrade the OS
+                    if user.navigation.screen == 2: 
+                        menuShortcut = ['^c', 'r', 'A', '']
+                        
+                        screenManager.menu.titleBar(texts.screens.titles.s_2_0); screenManager.menu.topMenu(menuShortcut, texts.menus.s_2_0)
+                        
+                        operations.software.check_OS_installers()
+                        
+                        user.navigation.response = screenManager.menu.inputMenu(menuShortcut, texts.menus.s_2_0, True, True)
+                        
+                        if user.navigation.response == -1 or user.navigation.response == '^c': 
+                            user.navigation.screen = 1
+                            
+                        elif user.navigation.response == 'A': 
+                            user.navigation.screen = 2.1
+                            
+                    elif user.navigation.screen == 2.1: 
+                        menuShortcut = ['^c', 'n', 'b', 'D']
+                        
+                        screenManager.menu.promptMenu(texts.screens.titles.s_2_1, texts.screens.messages.s_2_1, texts.menus.s_2_1, menuShortcut)
+                        
+                        if user.navigation.response == -1 or user.navigation.response == '^c': 
+                            user.navigation.screen = 2
+                        
+                        elif user.navigation.response == 'n' or user.navigation.response == '🚫': 
+                            user.navigation.screen = 2.2
+                    
+                    elif user.navigation.screen == 2.2: 
+                        menuShortcut = ['^c', '']
+                        
+                        screenManager.menu.promptMenu(texts.screens.titles.s_2_2, texts.screens.messages.s_2_2, texts.menus.s_2_2, menuShortcut)
+                        
+                        if user.navigation.response == -1 or user.navigation.response == '^c': 
+                            user.navigation.screen = 2.1
+                        
+                        elif user.navigation.response == '' or user.navigation.response == 'revert': 
+                            user.navigation.screen == 2.21
+                            
+                    elif user.navigation.screen == 2.21: 
+                        screenManager.menu.titleBar(texts.screens.titles.s_2_2_1); 
+                        
+                        if (operations.software.installer_branch.none()): 
+                            try: 
+                                info.err(texts.errors.screens.s_2_2_1)
+                            except KeyboardInterrupt: 
+                                user.navigation.screen = 2.1
+                        else: 
+                            user.navigation.screen = 2.1
+                        
+            if user.navigation.screen == -1: 
+                cls()
+        
+    def main(): 
+        screenManager.do()
+    
+    main()
+
+except SyntaxError as e: fail(texts.errors.default.syntaxerr + '\n' + str(e))
+except NameError as e: fail(texts.errors.default.syntaxerr + '\n' + str(e))
+except IndentationError as e: fail(texts.errors.default.syntaxerr + '\n' + str(e))
+except TypeError as e: fail(texts.errors.default.typeerr + '\n' + str(e))
+except AttributeError as e: fail(texts.errors.default.attributeerr + '\n' + str(e))