<s>[INST] I am working on a project to build an application that helps users to track their expenses. The application is designed to help individuals monitor and manage their expenses and stay within their budget. It will also provide insights into their spending habits.

The application should have the following features:

*   Allow users to add, edit and delete expenses.
*   Display a list of all the expenses.
*   Allow users to set a budget for a specific period (monthly, weekly, etc.).
*   Provide insights into the user's spending habits.

Here is a simplified version of the application's code:

```
# Class to represent an expense
class Expense:
    def __init__(self, name, amount, category):
        self.name = name
        self.amount = amount
        self.category = category

# Class to represent a budget
class Budget:
    def __init__(self, amount, period):
        self.amount = amount
        self.period = period

# Class to represent the expense tracker application
class ExpenseTracker:
    def __init__(self):
        self.expenses = []
        self.budget = None

    def add_expense(self, expense):
        self.expenses.append(expense)

    def delete_expense(self, expense):
        self.expenses.remove(expense)

    def set_budget(self, budget):
        self.budget = budget

    def get_expenses(self):
        return self.expenses
```

Can you help me improve this design?[/INST]