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Python

Posted by Maximilian Hill
.a{fill-rule:evenodd;}techdegree seal-36
Maximilian Hill
Python Development Techdegree Graduate 7,661 Points

It gives complicated explanation for ValueError

I am currently doing my master ticket project. I got it to raise a ValueError if the amount of tickets requested is g greater than the amount tickets remaining. The error response for that is also suitable. However, when passing along a string, it gives the actual error instead of the simple, user-friendly output that I like. Can someone help? My code is as follows

TICKET_PRICE = 10
tickets_remaining = 100  
while tickets_remaining >=1:
      print("They're are {} tickets remaining".format(tickets_remaining))
      user_name =input("Hello, welcome to Ticket Master! What is your name? ")
      number_of_tickets= input( "Well...{}, how many tickets would you like to buy?".format(user_name))
      try:
        number_of_tickets = int(number_of_tickets)
        if number_of_tickets > tickets_remaining:
          raise ValueError("Sorry, we only have {} tickets left".format(tickets_remaining))
        if number_of_tickets == str:
          raise ValueError ("Incorrect value. Please write a number")
      except ValueError as err:
          print("We ran into an issue. {}. Please try again.".format(err))
      else:
          total= (number_of_tickets * TICKET_PRICE)   
          print(" {}, your total is {}".format(user_name,total))
          proceed= input(" Would you like to proceed with purchase, Y for yes, N, for no:  ")
          if proceed.lower() == "y":
              #TODO: Gather Credit Card Information and process it. 
            print("SOLD! Your transaction is approved.")
            tickets_remaining = (tickets_remaining - number_of_tickets)
          else:
            print("{}, thank you for your consideration. Come again!".format(user_name))

print("Sorry, they're are no more tickets")

1 Answer

Steven Parker
Steven Parker
229,657 Points
Steven Parker
Steven Parker
229,657 Points

When you include the "err" value in the output, the technical system error message is being shown. But you can choose to display your own message and not include the system part if you want:

    print("We ran into an issue. {}. Please try again.".format(err))  # so instead of this
    print("Please try again and use only a numeric value.")           # you might use this
Maximilian Hill
.a{fill-rule:evenodd;}techdegree seal-36
Maximilian Hill
Python Development Techdegree Graduate 7,661 Points

Steven Parker If I chose to make a customer response for the value error associated with a string will make the value error I raise for the number of tickets available more than remaining. I want them to be independent.

Steven Parker
Steven Parker
229,657 Points
Steven Parker
Steven Parker
229,657 Points

Either way you do it, showing a message should not change the number of tickets. There must be some other issue.
Try making a snapshot of your workspace and post the link to it to allow accurate replication of the issue.