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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 signed_to_twos_comp(val: int, n_bits: int) -> int: """ Convert a signed integer to its "two's complement" representation. Args: val: signed integer n_bits: number of bits (which must reflect a whole number of bytes) Returns: unsigned integer: two's complement version """

    assert n_bits % 8 == 0, "Must specify a whole number of bytes"
    n_bytes = n_bits // 8
    b = val.to_bytes(n_bytes, byteorder=sys.byteorder, signed=True)
    return int.from_bytes(b, byteorder=sys.byteorder, signed=False)