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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 bits per component box. Parameters fptr : file Open file object. offset : int Start position of box in bytes. length : int Length of the box in bytes. Returns ------- BitsPerComponent Instance of the current bits per component box. """

        nbytes = length - 8
        data = fptr.read(nbytes)
        bpc = tuple(((x & 0x7f) + 1) for x in bytearray(data))
        signed = tuple(((x & 0x80) > 0) for x in bytearray(data))

        return cls(bpc, signed, length=length, offset=offset)