old_contents: def estimate_value(budget, exchange_rate):
      '''
  
      :param budget: float - amount of money you are planning to exchange.
      :param exchange_rate: float - unit value of the foreign currency.
      :return:
      '''
  
      pass
  
  def get_change(budget, exchanging_value):
      '''
  
      :param budget: float - amount of money you own.
      :param exchanging_value: int - amount of your money you want to exchange now.
      :return:
      '''
  
      pass
  
  
  def get_value(denomination, number_of_bills):
      '''
  
      :param denomination: int - the value of a bill.
      :param number_of_bills: int amount of bills you received.
      :return:
      '''
  
      pass
  
  
  def get_number_of_bills(budget, denomination):
      '''
  
      :param budget: float - the amount of money you are planning to exchange.
      :param denomination: int - the value of a single bill.
      :return:
      '''
  
      pass
  
  
  def exchangeable_value(budget, exchange_rate, spread, denomination):
      '''
  
      :param budget: float - the amount of your money you are planning to exchange.
      :param exchange_rate: float - the unit value of the foreign currency.
      :param spread: int - percentage that is taken as an exchange fee.
      :param denomination: int - the value of a single bill.
      :return:
      '''
  
      pass
new_contents: def estimate_value(budget, exchange_rate):
      '''
  
      :param budget: float - amount of money you are planning to exchange.
      :param exchange_rate: float - unit value of the foreign currency.
      :return:
      '''
  
      pass
  
  def get_change(budget, exchanging_value):
      '''
  
      :param budget: float - amount of money you own.
      :param exchanging_value: int - amount of your money you want to exchange now.
      :return:
      '''
  
      pass
  
  
  def get_value(denomination, number_of_bills):
      '''
  
      :param denomination: int - the value of a bill.
      :param number_of_bills: int amount of bills you received.
      :return:
      '''
  
      pass
  
  
  def get_number_of_bills(budget, denomination):
      '''
  
      :param budget: float - the amount of money you are planning to exchange.
      :param denomination: int - the value of a single bill.
      :return:
      '''
  
      pass
  
  
  def exchangeable_value(budget, exchange_rate, spread, denomination):
      '''
  
      :param budget: float - the amount of your money you are planning to exchange.
      :param exchange_rate: float - the unit value of the foreign currency.
      :param spread: int - percentage that is taken as an exchange fee.
      :param denomination: int - the value of a single bill.
      :return:
      '''
  
      pass
  
subject: Add EOL to file