How to use the pycares._cfficore.__init__.AresError function in pycares

def getnameinfo(self, ip_port, flags, callback):
        if not callable(callback):
            raise AresError("a callable is required")

        ip, port = ip_port

        if port < 0 or port > 65535:
            raise ValueError("port must be between 0 and 65535")

        sa4 = _ffi.new("struct sockaddr_in*")
        sa6 = _ffi.new("struct sockaddr_in6*")

        if 1 == _lib.ares_inet_pton(socket.AF_INET, s2b(ip), _ffi.addressof(sa4.sin_addr)):
            sa4.sin_family = socket.AF_INET
            sa4.sin_port = socket.htons(port)
            sa = sa4
        elif 1 == _lib.ares_inet_pton(socket.AF_INET6, s2b(ip), _ffi.addressof(sa6.sin6_addr)):
            sa6.sin6_family = socket.AF_INET6
            sa6.sin6_port = socket.htons(port)

def wrapper(self, *args, **kwds):
        if not self.channel:
            raise AresError("Channel has already been destroyed")
        return f(self, *args, **kwds)
    return wrapper

def _set_servers(self, servers):
        c = _ffi.new("struct ares_addr_node[%d]" % len(servers))
        for i in range(len(servers)):
            if 1 == _lib.ares_inet_pton(socket.AF_INET, s2b(servers[i]), _ffi.addressof(c[i].addr.addr4)):
                c[i].family = socket.AF_INET
            elif 1 == _lib.ares_inet_pton(socket.AF_INET6, s2b(servers[i]), _ffi.addressof(c[i].addr.addr6)):
                c[i].family = socket.AF_INET6
            else:
                raise ValueError("invalid IP address")

            if i > 0:
                c[i - 1].next = _ffi.addressof(c[i])

        r = _lib.ares_set_servers(self.channel, c)
        if r != _lib.ARES_SUCCESS:
            raise AresError()

def _get_servers(self):
        servers = _ffi.new("struct ares_addr_node **")

        r = _lib.ares_get_servers(self.channel, servers)
        if r != ARES_SUCCESS:
            raise AresError(errno.strerror(r))

        server_list = []
        server = _ffi.new("struct ares_addr_node **", servers[0])
        while True:
            if server == _ffi.NULL:
                break

            ip = _ffi.new("char []", _lib.INET6_ADDRSTRLEN)
            if _ffi.NULL != _lib.ares_inet_ntop(server.family, _ffi.addressof(server.addr), ip, _lib.INET6_ADDRSTRLEN):
                server_list.append(_ffi_string(ip, _lib.INET6_ADDRSTRLEN))

            server = server.next

        return server_list

if udp_port != -1:
            options.udp_port = udp_port
            optmask = optmask |  _lib.ARES_OPT_UDP_PORT

        if socket_send_buffer_size != -1:
            options.socket_send_buffer_size = socket_send_buffer_size
            optmask = optmask |  _lib.ARES_OPT_SOCK_SNDBUF

        if socket_receive_buffer_size != -1:
            options.socket_receive_buffer_size = socket_receive_buffer_size
            optmask = optmask |  _lib.ARES_OPT_SOCK_RCVBUF

        if sock_state_cb:
            if not callable(sock_state_cb):
                raise AresError("sock_state_cb is not callable")

            userdata = _ffi.new_handle(sock_state_cb)
            _global_set.add(userdata)     # must keep this alive!
            options.sock_state_cb = _sock_state_cb
            options.sock_state_cb_data = userdata
            optmask = optmask |  _lib.ARES_OPT_SOCK_STATE_CB

        if lookups:
            options.lookups = lookups
            optmask = optmask |  _lib.ARES_OPT_LOOKUPS

        if domains:
            strs = [_ffi.new("char[]", s2b(i)) for i in domains]
            c = _ffi.new("char *[%d]" % (len(domains) + 1))
            for i in range(len(domains)):
               c[i] = strs[i]

if domains:
            strs = [_ffi.new("char[]", s2b(i)) for i in domains]
            c = _ffi.new("char *[%d]" % (len(domains) + 1))
            for i in range(len(domains)):
               c[i] = strs[i]

            options.domains = c
            options.ndomains = len(domains)
            optmask = optmask |  _lib.ARES_OPT_DOMAINS

        if rotate == True:
            optmask = optmask |  _lib.ARES_OPT_ROTATE

        r = _lib.ares_init_options(channel, options, optmask)
        if r != _lib.ARES_SUCCESS:
            raise AresError()

        self.channel = channel[0]

        if servers:
            self._set_servers(servers)

        if local_ip:
            self.set_local_ip(local_ip)

        if local_dev:
            self.set_local_dev(local_dev)