@classmethod<EOL><INDENT>def parse(cls, fptr, offset, length):<DEDENT>
box = cls(length=length, offset=offset)<EOL>box.box = box.parse_superbox(fptr)<EOL>return box<EOL>
Parse colour group box.

        Parameters
        ----------
        fptr : file
            Open file object.
        offset : int
            Start position of box in bytes.
        length : int
            Length of the box in bytes.

        Returns
        -------
        ColourGroupBox
            Instance of the current colour group box.