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Python Introducing Lists Meet Lists Addition

Son-Hai Nguyen
Son-Hai Nguyen
2,481 Points
Posted by Son-Hai Nguyen
Son-Hai Nguyen
2,481 Points

print ("there are" , len(attendees) , "attendees currently") is actually printing a list?

Hi guys,

I tried 

print ("there are" + len(attendees) + "attendees currently")

and python gave me an TypeError: must be string bot integer. But how Craig changed the print function into

print ("there are" , len(attendees) , "attendees currently")

and it worked? is it in the () a list so that didnt care if it's an integer or a string?

Thanks guys.

3 Answers

Steven Parker
Steven Parker
231,271 Points
Steven Parker
Steven Parker
231,271 Points

The "print" function can handle multiple comma-separated arguments that are different types.

But to perform concatenation with the "+" operator, the operands on both sides of it must be strings.

Dan B
Dan B
6,155 Points
Dan B
Dan B
6,155 Points

There are also unnecessary spaces in your code.

The teacher's code was exactly:

print("There are", len(attendees), "attendees at the event")

Note that there are no spaces before the comma separators and no space after the print function. Also remember that using the addition sign means that you want python to add those parameters together. In this case you are trying to add a string and a function together with another string which will not work.

Son-Hai Nguyen
Son-Hai Nguyen
2,481 Points
Son-Hai Nguyen
Son-Hai Nguyen
2,481 Points

Thanks Steven. I’ve just tried it in Maya Python and it returned the same error as well.