docs: def brand(self, brand):
          """Sets the brand of this PaymentCard.
  
  
          :param brand: The brand of this PaymentCard.
          :type: str
          """
          allowed_values = ["visa", "mastercard", "americanExpress", "discover"]
          if brand is not None and brand not in allowed_values:
              raise ValueError(
                  "Invalid value for `brand` ({0}), must be one of {1}"
                  .format(brand, allowed_values)
              )
  
          self._brand = brand