new_contents: import warnings
  
  from . import models
  
  
  def Bankcard(card_number, expiry_date, name=None,
               cvv=None, start_date=None, issue_number=None):
      # This odd looking thing is to handle backwards compatibility with Oscar
      # 0.5 where the Bankcard class wasn't a model and lived in this utils
      # module.  As of 0.6, the Bankcard class is a model.
      #
      # We pretend to be a class here (hence the capitalisation), remap the
      # constructor args and return an instance of the new class.
      warnings.warn("The Bankcard class has moved to oscar.apps.payment.models",
                    DeprecationWarning)
      kwargs = {
          'number': card_number,
          'expiry_date': expiry_date,
          'name': name,
          'ccv': cvv,
          'start_date': start_date,
          'issue_number': issue_number
      }
      return models.Bankcard(**kwargs)
  
subject: Add backkwards-compatible Bankcard class factory