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Python Introducing Lists Using Lists Multidimensional Lists

problem iterating through the travel expenses list

This is my code:

travel_expenses = [
    [5.00, 2.75, 22.00, 0.00, 0.00],
    [24.75, 5.50, 15.00, 22.00, 8.00],
    [2.75, 5.50, 0.00, 29.00, 5.00],
print("travel_expenses: ")
week_number = 1
for week in travel_expenses:
    print("* Week #{}: ${}".format(week, sum(week))
          week_number += 1

# and this is the error i'm getting:
# File "expenses.py", line 10                                                                    
#   week_number += 1     

2 Answers

Clayton Perszyk
Clayton Perszyk
Treehouse Moderator 48,603 Points

You are missing a parenthesis in your second print statement and week_number += 1 is indented too much.

Thank you for the help but the other problem I've encountered is that the week_number doesn't print a numeric value next to "#" .

921 Points

The reason you are not seeing a numeric value next to # is because your in the second print statement should be format(week_number. You have format(week,