Three menu on tall version

_ * _ Coding #: UTF-8 _ * _ 
# Author: Wang Dian-yuan 
# Date: 2019/12/15 
'' ' 
three new menu functional requirements 
1. The need to save the file to the local content 
2. Users can regional content CRUD 
'' ' 
the MENU = { 
    ' Shanghai ': { 
        ' Minhang District ': { 
            ' old Minhang ': { 
                ' Zizhu Science Park ': {}, 
                ' Shanghai Jiao Tong University ': {} 
            } 
            ' new Minhang ': { 
                'River town': {}, 
                'Caohejing': {} 
            } 
        }, 
        'Huangpu District': { 
            'Bund': { 
                'Oriental Pearl': {}, 
                'Nanjing pedestrian Street': {}, 
                'Yuyuan': {} 
            },
            'Architecture': { 
                'People's Square': {},
                'Theater': {} 
            } 
        } 
    }, 
    'Shenzhen': { 
        'Futian District': { 
            'Huaqiang North': { 
                'Huaqiang Electronic City': {}, 
                'SEG Electronic City': {}, 
            }, 
            'walking Street': { 
                'East Gate walking Street': {}, 
                'lychee Park': {} 
            } 
        }, 
        'Nanshan District': { 
            'Science Park': { 
                'Nanshan Science and Technology Park': {} 
                ' Xili Technology Park ': {} 
            } 
            ' phone garden ': { 
                ' Cool Technology Park ': {}, 
                ' OPPO Technology Park ': {} 
            }
        },
    },
}
Open with ( 'three_level_menu', 'R & lt', encoding = 'UTF8') AS menu_read: 
    Zone = the eval (. menu_read.read () Strip ()) 
MSG = '' 'Enter Area * ******* ****** 
    input b return to the previous 
    input q to quit 
************************************************************ '' ' 
current_layer = Zone 
parent_layers = [] 
user_enter_quit = False 
the while not user_enter_quit: 
    Print (msg) 
    for Key in current_layer: 
        Print (Key) 
    user_enter the INPUT = ( "Please the INPUT:") 
    IF user_enter in current_layer: 
        parent_layers.append (current_layer) # each layer corresponds to the current dictionary added to the list in 
        current_layer = current_layer [user_enter] # dictionary assigned next layer the current layer 
    elif user_enter.lower () == 'b'and parent_layers != []:
        current_layer = parent_layers.pop () # default delete the last element of the list, and returns the element value. Does not increase the length of the list using the pop 
    elif user_enter.lower () == 'Q': 
        current_layer = parent_layers.pop (0) 
        user_enter_quit = True 
    elif user_enter Not in current_layer: # If user input is not in the dictionary, the user is inputted as key to add a new dictionary 
        IF user_enter == 'MOD': 
            original_zone the iNPUT = ( 'Please enter the modified region:') 
            mod_zone the iNPUT = ( 'Please enter content:') 
            current_layer [mod_zone] = current_layer [original_zone] 
            current_layer .pop (original_zone) 
        elif user_enter == 'REM': 
            rem_enter the iNPUT = ( 'Please enter the area to be deleted:') 
            current_layer.

            add_enter = input ( 'I'm sorry, no such region, please re-enter Add Region:') 
            current_layer [add_enter] = {#} After writing dictionary user input, the process proceeds to the next level, the user continues to enter the next prompt location 
            # print (current_layer [user_enter]) 
        the else: 
            Print ( 'last layer') 
    the else: 
        Print ( '! Please Enter Again') 
with Open ( 'three_level_menu', 'W', encoding = 'UTF8') AS menu_write: 
    menu_write.write (str (current_layer) .strip () )