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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 StaticAdd(cls, queue_urn, rdf_value, mutation_pool=None):
 """Adds an rdf value the queue. Adds an rdf value to a queue. Does not require that the queue be locked, or even open. NOTE: The caller is responsible for ensuring that the queue exists and is of the correct type. Args: queue_urn: The urn of the queue to add to. rdf_value: The rdf value to add to the queue. mutation_pool: A MutationPool object to write to. Raises: ValueError: rdf_value has unexpected type. """

    if not isinstance(rdf_value, cls.rdf_type):
      raise ValueError("This collection only accepts values of type %s." %
                       cls.rdf_type.__name__)
    if mutation_pool is None:
      raise ValueError("Mutation pool can't be none.")

    timestamp = rdfvalue.RDFDatetime.Now().AsMicrosecondsSinceEpoch()

    if not isinstance(queue_urn, rdfvalue.RDFURN):
      queue_urn = rdfvalue.RDFURN(queue_urn)

    mutation_pool.QueueAddItem(queue_urn, rdf_value, timestamp)