new_contents: class Account(object):
      def __init__(self, holder, number, balance,credit_line=1500): 
          self.Holder = holder 
          self.Number = number 
          self.Balance = balance
          self.CreditLine = credit_line
  
      def deposit(self, amount): 
          self.Balance = amount
  
      def withdraw(self, amount): 
          if(self.Balance - amount < -self.CreditLine):
              # coverage insufficient
              return False  
          else: 
              self.Balance -= amount 
              return True
  
      def balance(self): 
          return self.Balance
  
      def transfer(self, target, amount):
  	if(self.Balance - amount < -self.CreditLine):
              # coverage insufficient
              return False  
          else: 
              self.Balance -= amount 
              target.Balance += amount 
              return True
  
subject: Create OOP.py