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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 _create_replica(self, sysmeta_pyxb, sciobj_bytestream):
 """GMN handles replicas differently from native objects, with the main differences being related to handling of restrictions related to revision chains and SIDs. So this create sequence differs significantly from the regular one that is accessed through MNStorage.create(). """

        pid = d1_common.xml.get_req_val(sysmeta_pyxb.identifier)
        self._assert_is_pid_of_local_unprocessed_replica(pid)
        self._check_and_create_replica_revision(sysmeta_pyxb, "obsoletes")
        self._check_and_create_replica_revision(sysmeta_pyxb, "obsoletedBy")
        sciobj_url = d1_gmn.app.sciobj_store.get_rel_sciobj_file_url_by_pid(pid)
        sciobj_model = d1_gmn.app.sysmeta.create_or_update(sysmeta_pyxb, sciobj_url)
        self._store_science_object_bytes(pid, sciobj_bytestream)
        d1_gmn.app.event_log.create_log_entry(
            sciobj_model, "create", "0.0.0.0", "[replica]", "[replica]"
        )