code: def create(self, name, domain_name):
          
          name = self.wrap(self.resource.create(dict(name=name,
                                                     domain_name=domain_name)))
  
          self.add(name)
          return name
docs: Register a url (e.g. wallet.gem.co) for
  
          Args:
            name (str): human-readable wallet name (e.g. wallet)
            domain_name (str): the domain name to create subdomain on (e.g. gem.co)
              this domain must already be registered with Gem
  
          Returns: The new round.NetkiName