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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 capture_message(sock, get_channel=False):
 """ Captures a message from given socket. :param socket.socket sock: The socket to read a message from. :param bool get_channel: Find out which channel the message comes from. :return: The received message, or None on failure. """

    # Fetching the Arb ID, DLC and Data
    try:
        if get_channel:
            if HAS_NATIVE_SUPPORT:
                cf, addr = sock.recvfrom(CANFD_MTU)
                channel = addr[0] if isinstance(addr, tuple) else addr
            else:
                data = ctypes.create_string_buffer(CANFD_MTU)
                addr = ctypes.create_string_buffer(32)
                addrlen = ctypes.c_int(len(addr))
                received = libc.recvfrom(sock.fileno(), data, len(data), 0,
                                         addr, ctypes.byref(addrlen))
                cf = data.raw[:received]
                # Figure out the channel name
                family, ifindex = struct.unpack_from("Hi", addr.raw)
                assert family == AF_CAN
                data = struct.pack("16xi", ifindex)
                res = fcntl.ioctl(sock, SIOCGIFNAME, data)
                channel = ctypes.create_string_buffer(res).value.decode()
        else:
            cf = sock.recv(CANFD_MTU)
            channel = None
    except socket.error as exc:
        raise can.CanError("Error receiving: %s" % exc)

    can_id, can_dlc, flags, data = dissect_can_frame(cf)
    #log.debug('Received: can_id=%x, can_dlc=%x, data=%s', can_id, can_dlc, data)

    # Fetching the timestamp
    binary_structure = "@LL"
    res = fcntl.ioctl(sock, SIOCGSTAMP, struct.pack(binary_structure, 0, 0))

    seconds, microseconds = struct.unpack(binary_structure, res)
    timestamp = seconds + microseconds * 1e-6

    # EXT, RTR, ERR flags -> boolean attributes
    #   /* special address description flags for the CAN_ID */
    #   #define CAN_EFF_FLAG 0x80000000U /* EFF/SFF is set in the MSB */
    #   #define CAN_RTR_FLAG 0x40000000U /* remote transmission request */
    #   #define CAN_ERR_FLAG 0x20000000U /* error frame */
    is_extended_frame_format = bool(can_id & CAN_EFF_FLAG)
    is_remote_transmission_request = bool(can_id & CAN_RTR_FLAG)
    is_error_frame = bool(can_id & CAN_ERR_FLAG)
    is_fd = len(cf) == CANFD_MTU
    bitrate_switch = bool(flags & CANFD_BRS)
    error_state_indicator = bool(flags & CANFD_ESI)

    if is_extended_frame_format:
        #log.debug("CAN: Extended")
        # TODO does this depend on SFF or EFF?
        arbitration_id = can_id & 0x1FFFFFFF
    else:
        #log.debug("CAN: Standard")
        arbitration_id = can_id & 0x000007FF

    msg = Message(timestamp=timestamp,
                  channel=channel,
                  arbitration_id=arbitration_id,
                  is_extended_id=is_extended_frame_format,
                  is_remote_frame=is_remote_transmission_request,
                  is_error_frame=is_error_frame,
                  is_fd=is_fd,
                  bitrate_switch=bitrate_switch,
                  error_state_indicator=error_state_indicator,
                  dlc=can_dlc,
                  data=data)

    #log_rx.debug('Received: %s', msg)

    return msg