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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 _delete_nxos_db(self, unused, vlan_id, device_id, host_id, vni, is_provider_vlan):
 """Delete the nexus database entry. Called during delete precommit port event. """

        try:
            rows = nxos_db.get_nexusvm_bindings(vlan_id, device_id)
            for row in rows:
                nxos_db.remove_nexusport_binding(row.port_id, row.vlan_id,
                                    row.vni, row.switch_ip, row.instance_id)
        except excep.NexusPortBindingNotFound:
            return