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Python Python Basics Functions and Looping Raise an Exception

Katrine Guirguis
Katrine Guirguis
2,587 Points

Raise an Exeption: python challenge

How do I do this??

def suggest(product_idea):
    return product_idea + "inator"
product_idea = input("Did you write more than 3 characters?")
if more than 3 characters long != "yes":
    raise ValueError("Are you sure you wrote more than 3?")

2 Answers

Megan Amendola
.a{fill-rule:evenodd;}techdegree seal-36
Megan Amendola
Treehouse Teacher

Hi, Katrine! Let me review a few things before I jump into the code.

  • A string is made up of characters. There's a built-in function called len() that gives you the number of characters long a string is. You can pass in a string or a variable that is holding a string into the function to get the length of the string.
>>> len('string')
>>> test_string = 'string'
>>> len(test_string)
  • You have access to math symbols when programming. You can add +, subtract -, divide /, and multiply *. You can also check values based on < less than, > greater than, == equals, <= less than or equals, >= greater than or equals.
>>> 5 > 3
>>> 3 < 5
>>> 5 == 3
  • Whenever you see the keyword if you are probably going to need a conditional statement. A conditional statement checks if something is True and if it is, does some logic. You can also add another conditional with elif to see if something else is true. You can also end a conditional with an else to cover any other options.
num = 5
if num > 3:
    # do something if num if greater than 3
elif num < 3:
    # do something if num is less than 3
    # do something if neither of the above two conditions are True
    # like if the num was 3 this logic would run because 
    # it doesn't fit under either of the above conditions

Now, let's look at the code challenge. The first two sentences are fluff so we can ignore them. The last portion has the important information. (Tip: Also, always stick to what the code challenge is asking) Can you please raise a ValueError if the product_idea is less than 3 characters long? product_idea is a string.


  • product_idea is a string - Why is this important? If it's a string, then we can use string methods to interact with it. Hint: len()
  • if the product_idea is less than 3 characters long - Ok, we have the tools to translate this into code, so if len(product_idea) < 3:
  • raise a ValueError - This one you had - raise ValueError("Are you sure you wrote more than 3?")

Ok, now put it all together. This should all go inside of the given function.

def suggest(product_idea):
    if len(product_idea) < 3:
        raise ValueError("Are you sure you wrote more than 3?")
    return product_idea + "inator"