Python code

import datetime
import csv
from collections import defaultdict

# Class to handle expense tracking functionality
class ExpenseTracker:
    def _init_(self):
        self.expenses = []  # List to store all expenses

    def add_expense(self, amount, category, description):
        """
        Adds an expense to the tracker.
        :param amount: Expense amount (float).
        :param category: Expense category (string).
        :param description: Description of the expense (string).
        """
        expense = {
            "amount": amount,
            "category": category,
            "description": description,
            "date": datetime.datetime.now().strftime("%Y-%m-%d")
        }
        self.expenses.append(expense)
        print(f"Expense added: {description} - ${amount} ({category})")

    def view_expenses(self):
        """Displays the list of all recorded expenses."""
        if not self.expenses:
            print("No expenses recorded.")
            return
        print("\nExpense History:")
        for i, expense in enumerate(self.expenses, 1):
            print(f"{i}. {expense['date']} - {expense['description']} - ${expense['amount']} ({expense['category']})")

    def generate_summary(self):
        """Generates a summary report of expenses by category."""
        summary = defaultdict(float)
        for expense in self.expenses:
            summary[expense['category']] += expense['amount']
        print("\nExpense Summary:")
        for category, total in summary.items():
            print(f"{category}: ${total:.2f}")

    def export_to_csv(self, filename="expenses.csv"):
        """Exports expenses to a CSV file."""
        with open(filename, mode="w", newline="") as file:
            writer = csv.DictWriter(file, fieldnames=["date", "amount", "category", "description"])
            writer.writeheader()
            writer.writerows(self.expenses)
        print(f"Expenses exported to {filename}")

# Example usage of the ExpenseTracker application
def main():
    """Main function to run the ExpenseTracker application."""
    tracker = ExpenseTracker()
    while True:
        print("\nOptions:")
        print("1. Add Expense")
        print("2. View Expenses")
        print("3. Generate Summary")
        print("4. Export to CSV")
        print("5. Exit")
        choice = input("Choose an option: ")
        if choice == "1":
            try:
                amount = float(input("Enter amount: "))
                category = input("Enter category: ")
                description = input("Enter description: ")
                tracker.add_expense(amount, category, description)
            except ValueError:
                print("Invalid input. Please enter a valid number for the amount.")
        elif choice == "2":
            tracker.view_expenses()
        elif choice == "3":
            tracker.generate_summary()
        elif choice == "4":
            tracker.export_to_csv()
        elif choice == "5":
            print("Exiting application.")
            break
        else:
            print("Invalid choice. Please try again.")

if _name_ == "_main_":
    main()