# Source code for canlib.frame

    def dlc_to_bytes(dlc, canFd=False):
        """Convert DLC to number of bytes

        .. versionadded:: 1.7

        """
        if dlc < 9:
            bytes = dlc
        elif dlc == 9:
            bytes = 12
        elif dlc == 10:
            bytes = 16
        elif dlc == 11:
            bytes = 20
        elif dlc == 12:
            bytes = 24
        elif dlc == 13:
            bytes = 32
        elif dlc == 14:
            bytes = 48
        else:
            bytes = 64

        if canFd:
            return bytes
        else:
            return min(bytes, 8)

    def bytes_to_dlc(num_bytes, canFD=True):
        """Calculate minimum DLC that can hold number of bytes

        .. versionadded:: 1.18

        """
        if not canFD:
            return num_bytes
        if num_bytes < 8:
            return num_bytes
        if num_bytes <= 12:
            return 9
        if num_bytes <= 16:
            return 10
        if num_bytes <= 20:
            return 11
        if num_bytes <= 24:
            return 12
        if num_bytes <= 32:
            return 13
        if num_bytes <= 48:
            return 14
        return 15

    class Frame:
        """Represents a CAN message

        Args:
            id_: Message id
            data : Message data, will pad zero to match dlc (if dlc is given)
            dlc : Message dlc, default is calculated from number of data
            flags (`canlib.MessageFlag`): Message flags, default is 0
            timestamp : Optional timestamp
        """  # noqa: RST306

        __slots__ = ('id', 'data', 'dlc', 'flags', 'timestamp')
        _repr_slots = __slots__
        _eq_slots = __slots__[:-1]

        def __init__(self, id_, data, dlc=None, flags=0, timestamp=None):
            data = bytearray(data)

            if dlc is None:
                if len(data) <= 8:
                    dlc = len(data)
                elif len(data) <= 12:
                    dlc = 12
                elif len(data) <= 16:
                    dlc = 16
                elif len(data) <= 20:
                    dlc = 20
                elif len(data) <= 24:
                    dlc = 24
                elif len(data) <= 32:
                    dlc = 32
                elif len(data) <= 48:
                    dlc = 48
                else:
                    dlc = 64
                if dlc > len(data):
                    data.extend([0] * (dlc - len(data)))
            elif dlc <= 8:
                data.extend([0] * (dlc - len(data)))

            self.id = id_
            self.data = data
            self.dlc = dlc
            self.flags = flags
            self.timestamp = timestamp

        # in Python 2 both __eq__ and __ne__ must be implemented
        def __ne__(self, other):
            return not self == other

        def __eq__(self, other):
            if isinstance(other, Frame):
                return all(getattr(self, slot) == getattr(other, slot) for slot in self._eq_slots)
            else:
                return NotImplemented

        def __getitem__(self, index):
            slot = self.__slots__[index]
            return getattr(self, slot)

        def __setitem__(self, index, val):
            slot = self.__slots__[index]
            return setattr(self, slot, val)

        def __iter__(self):
            for slot in self.__slots__:
                yield getattr(self, slot)

        def __repr__(self):
            return '{cls}({kwargs})'.format(
                cls=self.__class__.__name__,
                kwargs=', '.join(slot + '=' + repr(getattr(self, slot)) for slot in self._repr_slots),
            )

    class LINFrame(Frame):
        """Represents a LIN message

        A `Frame` that also has an `info` attribute, which is a
        `linlib.MessageInfo` or `None`. This attribute is initialized via the `info`
        keyword-only argument to the constructor.

        """

        __slots__ = Frame.__slots__ + ('info',)

        # In python 3 we could just use:
        #
        # def __init__(self, *args, info=None, **kwargs):
        def __init__(self, *args, **kwargs):
            info = kwargs.pop("info", None)
            if 'timestamp' not in kwargs and info is not None:
                kwargs['timestamp'] = info.timestamp
            super().__init__(*args, **kwargs)
            self.info = info