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Calendar.py

"""This program will allow users to interact with a calendar"""

from time import sleep, strftime

user_first_name = "William"
calendar = []
def welcome():
  print "Hello " + user_first_name + " , welcome to your calendar!"
  print "The calendar is opening!"
  sleep(1)
  print "The local date is: " + strftime("%A, %B, %d, %Y")
  print "The local time is: " + strftime("%I, %M, %S, %p")
  sleep(1)
  print "What would you like to do?"
def start_calendar():
  welcome()
  start = True
  while start == True:
    user_choice = raw_input("A to Add, U to Update, V to View, D to Delete: ")
    user_choice.upper()
    if user_choice == 'V':
      if len(calendar.keys()) < 1:
        print "The calendar is empty!"
      else:
        print calendar
    elif user_choice == "U":
      date = raw_input("What date? ")
      update = raw_input("Please enter the update: ")
      calendar[date] = update
      print "The update was successful!"
      print calendar
    elif user_choice == "A":
      event = raw_input("Please enter the event: ")
      date = raw_input("Please enter the date in the MM/DD/YYYY format: ")
      if len(date) > 10 or int(date[6:]) < int(strftime("%Y")):
        print "You've entered an invalid date!"
        try_again = raw_input("Would you like to try again? (Y/N)")
        try_again = try_again.upper()
        if try_again == 'Y':
          continue
        else:
          start = False
      else:
        calendar[date] = event
        print "Event added successfully!"
        print calendar
    elif user_choice == "D":
      if len(calendar.keys()) < 1:
        print "The calendar is empty!"
      else:
        print calendar
        event = raw_input("What is the event: ")
        for date in calendar.keys():
          if event == calendar[date]:
            del calendar[date]
            print "The event was successfully deleted!"
          else:
            print "That event does not exist, be sure to enter the event exactly as it appears!"
    elif user_choice == "X":
      start = False
    else:
      print "An invalid command was entered, please try again!"
      start = False
start_calendar()