# Import necessary modules
import dataclasses
import pytest

# Define a dataclass for a simple BankAccount
@dataclasses.dataclass
class BankAccount:
    """Represents a simple bank account"""
    account_number: int
    account_holder: str
    balance: float = 0.0

    def deposit(self, amount: float) -> None:
        """Deposit money into the account"""
        self.balance += amount

    def withdraw(self, amount: float) -> None:
        """Withdraw money from the account"""
        if amount > self.balance:
            raise ValueError("Insufficient balance")
        self.balance -= amount

    def get_balance(self) -> float:
        """Get the current balance of the account"""
        return self.balance

# Define a function to create a new BankAccount
def create_account(account_number: int, account_holder: str) -> BankAccount:
    """Create a new BankAccount instance"""
    return BankAccount(account_number, account_holder)

# Define a function to perform a transaction
def perform_transaction(account: BankAccount, amount: float, is_deposit: bool) -> None:
    """Perform a transaction on the account"""
    if is_deposit:
        account.deposit(amount)
    else:
        account.withdraw(amount)

# Define a test function using pytest
def test_bank_account():
    """Test the BankAccount class"""
    account = create_account(12345, "John Doe")
    assert account.get_balance() == 0.0
    perform_transaction(account, 100.0, True)
    assert account.get_balance() == 100.0
    perform_transaction(account, 50.0, False)
    assert account.get_balance() == 50.0

# Run the test
pytest.main([__file__])

# Create a new BankAccount instance
account = create_account(12345, "John Doe")

# Perform some transactions
perform_transaction(account, 100.0, True)
perform_transaction(account, 50.0, False)

# Print the final balance
print("Final balance:", account.get_balance())