code: def get_host(self, unique_id):
      
      if unique_id in self.processes:
        return self.processes[unique_id].hostname
      logger.error("{0} not a known process".format(unique_id))
      raise NameError("{0} not a known process".format(unique_id))
docs: Gets the host of the process with `unique_id`.  If the deployer does not know of a process
      with `unique_id` then it should return a value of SOME_SENTINAL_VALUE
  
      :Parameter unique_id: the name of the process
      :raises NameError if the name is not  valid process