'Judge whether VPN target has existed'

def is_vpn_target_exist(self, target_type, value):

    if (target_type == 'export_extcommunity'):
        if ((value not in self.existing['vpn_target_export']) and (value not in self.existing['vpn_target_both'])):
            return False
        return True
    if (target_type == 'import_extcommunity'):
        if ((value not in self.existing['vpn_target_import']) and (value not in self.existing['vpn_target_both'])):
            return False
        return True
    return False
