def next(self):
    global name
    global age
    name = self.user_name.text
    age = get_num(self.user_age.text)
    if (age == False):
        self.user_age.text = ''
    else:
        self.manager.transition.direction = 'left'
        self.manager.current = '2'
def next(self):
    global name
    global age
    name = self.user_name.text
    age = get_num(self.user_age.text)
    if (age == False):
        self.user_age.text = 
    else:
        self.manager.transition.direction = 'left'
        self.manager.current = '2'