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Python

Posted by Mikaela Land
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Mikaela Land
Python Web Development Techdegree Student 2,324 Points

What is a BaseException?

I keep getting this when I input a number over 100, what does it mean and what do I do with it?:

Traceback (most recent call last):
File "masterticket.py", line 13, in <module>
raise ("There are only {} tickets remaining".format(tickets_remaining))
TypeError: exceptions must derive from BaseException 

    try:  
        prompt = int (input (" Hello {}.  How many tickets would you like?   ".format(user_name)))
        #rase error text in the output
        if prompt > tickets_remaining:
            raise ("There are only {} tickets remaining".format(tickets_remaining))
    except ValueError as err:
        print ("{}".format (err))

1 Answer

andren
andren
28,558 Points

When you raise an exception you have to provide a type of exception, like ValueError, TypeError, etc and not just a pure string like you are doing in your code. BaseException is a class which all other exception types inherit from, it can be used to create custom exception types as well, but that is a more complex topic which you likely have not gotten to yet.

If you change your raise statement to something like this:

raise ValueError("There are only {} tickets remaining".format(tickets_remaining))

Then that error should go away.

Mikaela Land
.a{fill-rule:evenodd;}techdegree
Mikaela Land
Python Web Development Techdegree Student 2,324 Points

Oh I just missed that. I forgot. Thanks!