Как рассчитать оставшиеся дни, если я попрошу пользователя ввести дату события с этого момента

Question

Я делаю проект, чтобы создать программу с графическим интерфейсом для пользователей, чтобы рассчитать оставшиеся дни до достижения события. У меня возникла проблема с вычислением оставшейся даты между датой события пользователя и сейчас.

from tkinter import * 
import datetime

def save_info():
    eventname_info = eventname.get()
    eventyear_info = eventyear.get()
    eventyear_info = str(eventyear_info)
    eventmonth_info = eventmonth.get()
    eventmonth_info = str(eventmonth_info)
    eventday_info = eventday.get()
    eventday_info = str(eventday_info)
    print(eventname_info, eventyear_info, eventmonth_info, eventday_info)

def calculate():


def combine_funs():
    save_info()
    calculate()


    file = open("actualdata.txt", "w")
    file.write(eventname_info)
    file.write(eventyear_info)
    file.write(eventmonth_info)
    file.write(eventday_info)
    file.close()
    print(" Event ", eventname_info, " has been record successfully")

    eventname_entry.delete(0, END)
    eventyear_entry.delete(0, END)
    eventmonth_entry.delete(0, END)
    eventday_entry.delete(0, END)

screen = Tk()
screen.geometry("500x500")
screen.title("Welcome to the Countdown module")
heading = Label(text = "Welcome to the Countdown module", width = "500", height = "2")
heading.pack()

eventname_text = Label(text = "Event name:")
eventyear_text = Label(text = "Event year:")
eventmonth_text = Label(text = "Event month:")
eventday_text = Label(text = "Event day:")

eventname_text.place(x = 15, y = 70)
eventyear_text.place(x = 15, y = 140)
eventmonth_text.place(x = 15, y = 210)
eventday_text.place(x = 15, y = 280)

eventname = StringVar()
eventyear = IntVar()
eventmonth = IntVar()
eventday = IntVar()

eventname_entry = Entry(textvariable = eventname, width = "30")
eventyear_entry = Entry(textvariable = eventyear, width = "30")
eventmonth_entry = Entry(textvariable = eventmonth, width = "30")
eventday_entry = Entry(textvariable = eventday,width = "30")

eventname_entry.place(x = 15, y = 100)
eventyear_entry.place(x = 15, y = 170)
eventmonth_entry.place(x = 15, y = 240)
eventday_entry.place(x = 15, y = 310)

addbutton = Button(screen,text = "Add timer", width = "30", height = "2", command = combine_funs,)
addbutton.place(x = 15, y = 390)

Окончательным результатом будет название события и оставшиеся дни.

Answer 1

использовать библиотеку даты и времени,

from datetime import datetime

current_date = str(datetime.now().date()) # will give you current date
user_date = input("enter date in 2019-05-13 format")
remaining_days = user_date - current_date # won't work directly, preprocess it before