Password show and hide errors AttributeError: 'super' object has no attribute '__getattr__'

I have created a login form, on a password section there is a checkbox to check whether the user needs to show or hide their password. When I input a random password and checked, unfortunately, an error showed:

self.root.ids.password.password = False
   File "kivy\properties.pyx", line 864, in kivy.properties.ObservableDict.__getattr__
 AttributeError: 'super' object has no attribute '__getattr__'

def show_password(self, checkbox, value):
        if value:
            self.root.ids.password.password = False
            self.root.ids.password_text.text = 'Hide password'
        else:
            self.root.ids.password.password = True
            self.root.ids.password_text.text = 'Show password'


MDFloatLayout:
            size_hint: .79, .08
            pos_hint: {"center_x": .5, "center_y": .32}
            
            MDLabel:
                text: "Password"
                font_size: "14sp"
                pos_hint: {"center_x": .5, "center_y": 1.2}
            
            TextInput:
                id: password
               # hint_text: 'Password'
                size_hint_y: .75
                pos_hint: {"center_x": .49, "center_y": .6}
                background_color: 0,0,0,0
                cursor_color: 0,0,0,1
                cursor_width: "2sp"
                font_size: "17sp"
                multiline: False
                password: True
            Image: 
                source: "media/key.png"
                pos_hint: {"center_x": .96, "center_y": .5}
                size_hint: .4, .4 
                
            MDFloatLayout:
                pos_hint:  {"center_x": .5, "center_y": 0} 
                size_hint_y:  .03
                md_bg_color: 120/255, 120/255, 120/255, 1
    
        MDCheckbox:
            size_hint: None, None          
            size: '48dp', '48dp'
            pos_hint: {'center_x': 0.18,'center_y': 0.25}
            on_active: app.show_password(*args)
        
        MDLabel:
            id: password_text
            text: 'Show Password'
            pos_hint: {'center_x': 0.75,'center_y': 0.25}

How to fixed it?