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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_evpn_table(self):
 """Returns global EVPN table. Creates the table if it does not exist. """

        evpn_table = self._global_tables.get(RF_L2_EVPN)
        # Lazy initialization of the table.
        if not evpn_table:
            evpn_table = EvpnTable(self._core_service, self._signal_bus)
            self._global_tables[RF_L2_EVPN] = evpn_table
            self._tables[(None, RF_L2_EVPN)] = evpn_table

        return evpn_table