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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 _unpack_lookupswitch(bc, offset):
 """ function for unpacking the lookupswitch op arguments """


    jump = (offset % 4)
    if jump:
        offset += (4 - jump)

    (default, npairs), offset = _unpack(_struct_ii, bc, offset)

    switches = list()
    for _index in range(npairs):
        pair, offset = _unpack(_struct_ii, bc, offset)
        switches.append(pair)

    return (default, switches), offset