code: def StaticAdd(cls,
                  collection_urn,
                  rdf_value,
                  timestamp=None,
                  suffix=None,
                  mutation_pool=None):
      
      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.")
      if timestamp is None:
        timestamp = rdfvalue.RDFDatetime.Now()
      if isinstance(timestamp, rdfvalue.RDFDatetime):
        timestamp = timestamp.AsMicrosecondsSinceEpoch()
  
      if not rdf_value.age:
        rdf_value.age = rdfvalue.RDFDatetime.Now()
  
      if not isinstance(collection_urn, rdfvalue.RDFURN):
        collection_urn = rdfvalue.RDFURN(collection_urn)
  
      _, timestamp, suffix = mutation_pool.CollectionAddItem(
          collection_urn, rdf_value, timestamp, suffix=suffix)
  
      return timestamp, suffix
docs: Adds an rdf value to a collection.
  
      Adds an rdf value to a collection. Does not require that the collection be
      open. NOTE: The caller is responsible for ensuring that the collection
      exists and is of the correct type.
  
      Args:
        collection_urn: The urn of the collection to add to.
        rdf_value: The rdf value to add to the collection.
        timestamp: The timestamp (in microseconds) to store the rdf value at.
          Defaults to the current time.
        suffix: A 'fractional timestamp' suffix to reduce the chance of
          collisions. Defaults to a random number.
        mutation_pool: A MutationPool object to write to.
  
      Returns:
        The pair (timestamp, suffix) which identifies the value within the
        collection.
  
      Raises:
        ValueError: rdf_value has unexpected type.