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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def get_host(self, unique_id):
 """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 """

    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))