old_contents: def exchange_money(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: float - exchanged value of the foreign currency you can receive.
      """
  
      return budget / exchange_rate
  
  
  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: float - amount left of your starting currency after exchanging.
      """
  
      return budget - exchanging_value
  
  
  def get_value_of_bills(denomination, number_of_bills):
      """
  
      :param denomination: int - the value of a bill.
      :param number_of_bills: int amount of bills you received.
      :return: int - total value of bills you now have.
      """
  
      return number_of_bills * denomination
  
  
  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: int - number of bills after exchanging all your money.
      """
  
      return int(budget / denomination)
  
  
  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: int - maximum value you can get.
      """
  
      exchange_fee = (exchange_rate / 100) * spread
      actual_rate = exchange_rate + exchange_fee
      exchangeable_amount = int((budget / actual_rate) / denomination)
      return exchangeable_amount * denomination
  
  
  def non_exchangeable_value(budget, exchange_rate, spread, denomination):
      """
  
      :param budget: float - amount of money you are planning to exchange.
      :param exchange_rate: float - unit value of the foreign currency.
      :param spread: int - the percentage taken as an exchange fee.
      :param denomination:  int - the value of a single bill.
      :return: int - non_exchangeable value.
      """
  
      exchange_fee = (exchange_rate / 100) * spread
      actual_rate = exchange_rate + exchange_fee
      non_exchangeable_amount = int((budget / actual_rate) % denomination)
      return non_exchangeable_amount
  
new_contents: def exchange_money(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: float - exchanged value of the foreign currency you can receive.
      """
  
      return budget / exchange_rate
  
  
  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: float - amount left of your starting currency after exchanging.
      """
  
      return budget - exchanging_value
  
  
  def get_value_of_bills(denomination, number_of_bills):
      """
  
      :param denomination: int - the value of a bill.
      :param number_of_bills: int amount of bills you received.
      :return: int - total value of bills you now have.
      """
  
      return number_of_bills * denomination
  
  
  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: int - number of bills after exchanging all your money.
      """
  
      return int(budget / denomination)
  
  
  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: int - maximum value you can get.
      """
  
      exchange_fee = (exchange_rate / 100) * spread
      actual_rate = exchange_rate + exchange_fee
      exchangeable_amount = int((budget / actual_rate) / denomination)
      return exchangeable_amount * denomination
  
  
  def non_exchangeable_value(budget, exchange_rate, spread, denomination):
      """
  
      :param budget: float - amount of money you are planning to exchange.
      :param exchange_rate: float - unit value of the foreign currency.
      :param spread: int - the percentage taken as an exchange fee.
      :param denomination:  int - the value of a single bill.
      :return: int - the value that cannot be exchanged, due to the denomination.
      """
  
      exchange_fee = (exchange_rate / 100) * spread
      actual_rate = exchange_rate + exchange_fee
      non_exchangeable_amount = int((budget / actual_rate) % denomination)
      return non_exchangeable_amount
  
subject: Update exercises/concept/currency-exchange/.meta/exemplar.py