input: Write a function to simulate a simple ATM machine by defining an account class with necessary functions and an ATM class with functions to create accounts, deposit money, withdraw money, and print the balance.
  assert atm_simulation() == "\nJohn Balance: 2000\nDoe Balance: 2990"
  assert atm_simulation() == "\nAlice Balance: 1500\nBob Balance: 900"
  assert atm_simulation() == "\nEve Balance: 3000\nFrank Balance: 3800"
  assert atm_simulation() == "\nGrace Balance: 1000\nHarry Balance: 990"
  assert atm_simulation() == "\nIvy Balance: 0"
output: class Account:
      def __init__(self, name, balance=0):
          self.name = name
          self.balance = balance
  
      def deposit(self, amount):
          self.balance += amount
  
      def withdraw(self, amount):
          if amount <= self.balance:
              self.balance -= amount
          else:
              raise ValueError("Insufficient funds")
  
      def get_balance(self):
          return self.balance
  
  class ATM:
      def __init__(self):
          self.accounts = {}
  
      def create_account(self, name, initial_balance=0):
          if name in self.accounts:
              raise ValueError("Account already exists")
          self.accounts[name] = Account(name, initial_balance)
  
      def deposit(self, name, amount):
          if name not in self.accounts:
              raise ValueError("Account does not exist")
          self.accounts[name].deposit(amount)
  
      def withdraw(self, name, amount):
          if name not in self.accounts:
              raise ValueError("Account does not exist")
          self.accounts[name].withdraw(amount)
  
      def print_balance(self, name):
          if name not in self.accounts:
              raise ValueError("Account does not exist")
          return f"{name} Balance: {self.accounts[name].get_balance()}"
  
  def atm_simulation():
      atm = ATM()
      atm.create_account("John", 2000)
      atm.create_account("Doe", 3000)
      atm.withdraw("Doe", 10)
      return f"\n{atm.print_balance('John')}\n{atm.print_balance('Doe')}"