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Python Introducing Lists Using Lists Multidimensional Lists

week_number <--- is that a variable?

is week_number a variable? How would week, week_number and travel_expenses be connected and or how would the loop (for week in travel_expenses) know what information to loop through if week_number is a variable and not a function?

I don't even know if my question makes sense, that's how confused I am

1 Answer

Steven Parker
Steven Parker
231,275 Points

You're exactly right, "week_number" is indeed a variable. So is "week", but they are not connected. But both of them are used to hold a number.

The term after the word "in" tells a loop what to loop through. it's called the "iterable". In this loop the iterable is "travel_expenses", which is a variable that contains a list of values. So the loop goes through the list, and assigns each value (one at a time) to "week".

Does that clear it up? Add a comment if you need more help with this.

Stephanie Tabor
Stephanie Tabor
2,944 Points

When I was watching the video, I had the same question. Does week_number = 1 as in one list in the travel_expenses iterable? Or does week_number = 1 literally mean the number 1?

Steven Parker
Steven Parker
231,275 Points

A reference to another variable would have to have the variable's name. A literal "1" always represents just the number 1.