new_contents: """
  coin.py
  Contains a class defining a currency (coin).
  """
  
  
  class Coin:
      """
      A container for a coin
      """
  
      def __init__(self, currency_id, currency_name, amount):
          self.currency_id = int(currency_id)
          self.currency_name = str(currency_name)
          self.amount = float(amount)
subject: add coin class