Learn Lambda Functions by Building an Expense Tracker - Step 13

Tell us what’s happening:

Describe your issue in detail here.
I did this but it’s not working

Your code so far

def add_expense(expenses, amount, category):
    expenses.append({'amount': amount, 'category': category})
def print_expenses(expenses):
    for expense in expenses:
        print(f'Amount: {expense["amount"]}, Category: {expense["category"]}')

def total_expenses(expenses):

# User Editable Region

test = (map(lambda x: x * 2, [2, 3, 5, 8])
print map(test(3))

# User Editable Region

expenses = []

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Challenge Information:

Learn Lambda Functions by Building an Expense Tracker - Step 13

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  • The array goes into the print call as the second argument
  • You are no longer using just 3 as the argument for the lambda
  • Remember to wrap the map function into prints parenthesis
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print(test (test = map(lambda x: x * 2))), it’s not working

Modify your print() call

Do not modify the “test =” line

test = lambda x: x * 2
print(test map(3))

Getting closer!

print the result of calling map() with test as the first argument, and [2, 3, 5, 8] as the second argument.

Where is [2, 3, 5, 8] ?

Do you have any questions about the instructions or terms?

Here’s how to call a function with two arguments:

function(arg1, arg2)


1 Like