请问，此程序提示有值误差问题，有哪位能来帮我解决一下？

Question

from tkinter import Tk,Canvas
from datetime import date,datetime
def get_events():
    list_events=[]
    with open('events.txt')as file:
        for line in file:
            line=line.rstrip('\n')
            current_event=line.split(',')
            event_date=datetime.strptime(current_event[1],'%d/%m/%y').date()
            current_event[1]=event_date
            list_events.append(current_event)
    return list_events
def days_between_dates(date1,date2):
    time_between=str(date1-date2)
    number_of_days=time_between.split(' ')
    return number_of_days[0]
root=Tk()
c=Canvas(root,width=800,height=800,bg='black')
c.pack()
c.create_text(100,50,anchor='w',fill='orange',font='Arial 28 bold underline',text='My Countdown Calendar')
events=get_events()
today=date.today()
vertical_space=100
for event in events:
    event_name=event[0]
    days_until=days_between_dates(event[1],today)
    display='It is %s days until %s'%(days_until,event_name)
    c.create_text(100,vertical_space,anchor='w',fill='lightblue',font='Arial 28 bold',text=display)
    vertical_space =vertical_space+30

Traceback (most recent call last):
  File "/Users/fym/Desktop/方嘉铭 编程/倒计时日历.py", line 21, in <module>
    events=get_events()
  File "/Users/fym/Desktop/方嘉铭 编程/倒计时日历.py", line 9, in get_events
    event_date=datetime.strptime(current_event[1],'%d/%m/%y').date()
  File "/Library/Frameworks/Python.framework/Versions/3.10/lib/python3.10/_strptime.py", line 568, in _strptime_datetime
    tt, fraction, gmtoff_fraction = _strptime(data_string, format)
  File "/Library/Frameworks/Python.framework/Versions/3.10/lib/python3.10/_strptime.py", line 352, in _strptime
    raise ValueError("unconverted data remains: %s" %
ValueError: unconverted data remains: 22

events.txt
My birthday,09/07/2012