'Config ntp'

def config_ntp(self):

    if (self.state == 'present'):
        if (self.address and (not self.conf_exsit)):
            if (self.is_preferred == 'enable'):
                is_preferred = 'true'
            else:
                is_preferred = 'false'
            self.set_ntp(self.ip_ver, self.address, self.peer_type, self.vpn_name, self.key_id, is_preferred, self.interface)
            self.changed = True
    elif self.address:
        self.set_ntp(self.ip_ver, self.address, self.peer_type, self.vpn_name, '', '', '')
        self.changed = True
