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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 _twosComplement(x, bits=16):
 """Calculate the two's complement of an integer. Then also negative values can be represented by an upper range of positive values. See https://en.wikipedia.org/wiki/Two%27s_complement Args: * x (int):
 input integer. * bits (int):
 number of bits, must be > 0. Returns: An int, that represents the two's complement of the input. Example for bits=8: ==== ======= x returns ==== ======= 0 0 1 1 127 127 -128 128 -127 129 -1 255 ==== ======= """

    _checkInt(bits, minvalue=0, description='number of bits')
    _checkInt(x, description='input')
    upperlimit = 2 ** (bits - 1) - 1
    lowerlimit = -2 ** (bits - 1)
    if x > upperlimit or x < lowerlimit:
        raise ValueError('The input value is out of range. Given value is {0}, but allowed range is {1} to {2} when using {3} bits.' \
            .format(x, lowerlimit, upperlimit, bits))

    # Calculate two'2 complement
    if x >= 0:
        return x
    return x + 2 ** bits