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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 parse(cls, fptr, offset, length):
 """Parse JPEG 2000 header box. Parameters fptr : file Open file object. offset : int Start position of box in bytes. length : int Length of the box in bytes. Returns ------- JP2HeaderBox Instance of the current JP2 header box. """

        box = cls(length=length, offset=offset)

        # The JP2 header box is a superbox, so go ahead and parse its child
        # boxes.
        box.box = box.parse_superbox(fptr)

        return box