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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_l2vpnfs_table(self):
 """Returns global L2VPN Flow Specification table. Creates the table if it does not exist. """

        l2vpnfs_table = self._global_tables.get(RF_L2VPN_FLOWSPEC)
        # Lazy initialization of the table.
        if not l2vpnfs_table:
            l2vpnfs_table = L2VPNFlowSpecTable(self._core_service,
                                               self._signal_bus)
            self._global_tables[RF_L2VPN_FLOWSPEC] = l2vpnfs_table
            self._tables[(None, RF_L2VPN_FLOWSPEC)] = l2vpnfs_table

        return l2vpnfs_table