Create a class called BankAccount
Create a constructor that takes in an integer and assigns this to a `balance`
property.
Create a method called `deposit` that takes in cash deposit amount and updates
the balance accordingly.
Create a method called `withdraw` that takes in cash withdrawal amount
Create a class called BankAccount
Create a constructor that takes in an integer and assigns this to a `balance`
property.
Create a method called `deposit` that takes in cash deposit amount and updates
the balance accordingly.
Create a method called `withdraw` that takes in cash withdrawal