class BankAccount:
    def set_details(self, name, balance=0):
        self.name = name
        self.balance = balance

    def display(self):
         print(self.name, self.balance)

    def withdraw(self, amount):
        self.balance -= amount

    def deposit(self, amount):
        self.balance += amount
    
a1 = BankAccount()
a1.set_details('Mike', 200)

a2 = BankAccount()
a2.set_details('Tom')

a1.display()
a2.display()

a1.withdraw(100)
a2.deposit(500)

a1.display()
a2.display()