Expense Tracker

Build an expense tracker that lets users add expenses with a category and amount, view a summary by category, and save/load expenses to/from a CSV file so data persists between runs.

Requirements

1. Store each expense as a dictionary with: date, category, amount, description.
2. Implement adding a new expense via user input.
3. Implement viewing all expenses in a readable table format.
4. Implement a summary showing total spending per category.
5. Save expenses to a CSV file using the csv module.
6. Load expenses from the CSV file on startup if it exists.
7. Handle file-not-found errors gracefully when loading.

import csv
import os
from datetime import date

FILENAME = "expenses.csv"
expenses = []

def add_expense(category, amount, description):
    expenses.append({
        "date": str(date.today()),
        "category": category,
        "amount": float(amount),
        "description": description
    })
    print("Expense added.")

def view_expenses():
    if not expenses:
        print("No expenses recorded.")
        return
    print(f"{'Date':<12}{'Category':<15}{'Amount':<10}{'Description'}")
    for e in expenses:
        print(f"{e['date']:<12}{e['category']:<15}{e['amount']:<10.2f}{e['description']}")

def category_summary():
    totals = {}
    for e in expenses:
        totals[e["category"]] = totals.get(e["category"], 0) + e["amount"]
    print("\n--- Category Summary ---")
    for cat, total in totals.items():
        print(f"{cat}: ${total:.2f}")
    print(f"Total spent: ${sum(totals.values()):.2f}")

def save_expenses():
    with open(FILENAME, "w", newline="") as f:
        writer = csv.DictWriter(f, fieldnames=["date", "category", "amount", "description"])
        writer.writeheader()
        writer.writerows(expenses)
    print("Expenses saved.")

def load_expenses():
    global expenses
    if not os.path.exists(FILENAME):
        return
    with open(FILENAME, "r", newline="") as f:
        reader = csv.DictReader(f)
        for row in reader:
            row["amount"] = float(row["amount"])
            expenses.append(row)

def main():
    load_expenses()
    while True:
        print("\n--- Expense Tracker ---")
        print("1. Add Expense")
        print("2. View Expenses")
        print("3. Category Summary")
        print("4. Save & Exit")
        choice = input("Choose an option: ")

        if choice == "1":
            category = input("Category: ")
            amount = input("Amount: ")
            description = input("Description: ")
            try:
                add_expense(category, float(amount), description)
            except ValueError:
                print("Invalid amount.")
        elif choice == "2":
            view_expenses()
        elif choice == "3":
            category_summary()
        elif choice == "4":
            save_expenses()
            print("Goodbye!")
            break
        else:
            print("Invalid option.")

if __name__ == "__main__":
    main()

50 XP on completion Back to Day 5

Your Code

import csv
import os
from datetime import date

FILENAME = "expenses.csv"
expenses = []

def add_expense(category, amount, description):
    # TODO: append a new expense dict with today's date
    pass

def view_expenses():
    # TODO: print all expenses
    pass

def category_summary():
    # TODO: print total amount per category
    pass

def save_expenses():
    # TODO: write expenses to FILENAME using csv
    pass

def load_expenses():
    # TODO: read expenses from FILENAME if it exists
    pass

Output

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