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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 __hammingDistance(s1, s2):
        '''
        Finds the Hamming distance between two strings.

        @param s1: string
        @param s2: string
        @return: the distance
        @raise ValueError: if the lenght of the strings differ
        '''

        l1 = len(s1)
        l2 = len(s2)

        if l1 != l2:
            raise ValueError("Hamming distance requires strings of same size.")

        return sum(ch1 != ch2 for ch1, ch2 in zip(s1, s2))