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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 bitwise_xor(bs0: str, bs1: str) -> str: """ A helper to calculate the bitwise XOR of two bit string :param bs0: String of 0's and 1's representing a number in binary representations :param bs1: String of 0's and 1's representing a number in binary representations :return: String of 0's and 1's representing the XOR between bs0 and bs1 """

    if len(bs0) != len(bs1):
        raise ValueError("Bit strings are not of equal length")
    n_bits = len(bs0)
    return PADDED_BINARY_BIT_STRING.format(xor(int(bs0, 2), int(bs1, 2)), n_bits)