code: def _container_registration(self, alias):
          
          containers = Container.find_by_name(self._client_session, alias)
  
          def validate_name(name):
              valid = True
              if name in containers:
                  valid = False
  
              return valid
  
          count = 1
          container_name = "{0}-0{1}".format(alias, count)
          while not validate_name(container_name):
              count += 1
              container_index = count if count > 10 else "0{0}".format(count)
              container_name = "{0}-{1}".format(alias, container_index)
  
          return container_name
docs: Check for an available name and return that to the caller.