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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 _adjust(a, a_offset, b):
 """ a = bytearray a_offset = int b = bytearray """

    x = (b[-1] & 0xFF) + (a[a_offset + len(b) - 1] & 0xFF) + 1
    a[a_offset + len(b) - 1] = ctypes.c_ubyte(x).value
    x >>= 8

    for i in range(len(b)-2, -1, -1):
        x += (b[i] & 0xFF) + (a[a_offset + i] & 0xFF)
        a[a_offset + i] = ctypes.c_ubyte(x).value
        x >>= 8