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Python Python Collections (2016, retired 2019) Dictionaries Teacher Stats

Posted by Omar G.
Omar G.
3,620 Points

The num_teachers function should return an integer for how many teachers are in the dict

Maybe I am misunderstanding the question but in this challenge, it wants us to return how many teachers are in the dictionary. Each teacher is a key so it wants us to return how many keys are in the dictionary as a number(int). So I wrote this code which does that.

this is my code:

def num_teachers(teachers):
    print (len(teachers.keys()))

This using the sample list it printed 2 teachers and I added a few more teachers (as keys) and courses just to check and returned everything properly. But it says the number of teachers is wrong. Am I understanding the challenge incorrectly? Any hints to point me in the right direction would be appreciated.

1 Answer

andren
andren
28,558 Points
andren
andren
28,558 Points

The challenge asks you to return the number of teachers, you are printing the number of teachers. The return keyword and print function might look more or less identical when used in the REPL (due to returned values being printed out automatically) but they actually do very different things. Simply put return passes the value back to the code that called the function, while print outputs the value to the console.

If you return the length like this:

def num_teachers(teachers):
    return len(teachers.keys())

Then your code will pass.

Edit: Added a simple explanation about what return and print does.

Omar G.
Omar G.
3,620 Points

Thank you so much. I can't believe I didn't notice that. Thank you so much!