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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 main() -> None: """ Command-line validation checks. """

    _ = """
    print(twos_comp_to_signed(0, n_bits=32))  # 0
    print(twos_comp_to_signed(2 ** 31 - 1, n_bits=32))  # 2147483647
    print(twos_comp_to_signed(2 ** 31, n_bits=32))  # -2147483648 == -(2 ** 31)
    print(twos_comp_to_signed(2 ** 32 - 1, n_bits=32))  # -1
    print(signed_to_twos_comp(-1, n_bits=32))  # 4294967295 = 2 ** 32 - 1
    print(signed_to_twos_comp(-(2 ** 31), n_bits=32))  # 2147483648 = 2 ** 31 - 1
    """  # noqa
    testdata = [
        "hello",
        1,
        ["bongos", "today"],
    ]
    for data in testdata:
        compare_python_to_reference_murmur3_32(data, seed=0)
        compare_python_to_reference_murmur3_64(data, seed=0)
    print("All OK")