code: def domain_name(self, domain_name):
          
  
          if domain_name is None:
              raise ValueError("Invalid value for `domain_name`, must not be `None`")
          if len(domain_name) > 255:
              raise ValueError("Invalid value for `domain_name`, length must be less than `255`")
          if len(domain_name) < 1:
              raise ValueError("Invalid value for `domain_name`, length must be greater than or equal to `1`")
  
          self._domain_name = domain_name
docs: Sets the domain_name of this RegisterDomainRequest.
          A domain name as described in RFC-1034 that will be registered with ApplePay
  
          :param domain_name: The domain_name of this RegisterDomainRequest.
          :type: str