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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 strings_equal(s1, s2):
 """ Timing-attack resistant string comparison. Normal comparison using == will short-circuit on the first mismatching character. This avoids that by scanning the whole string, though we still reveal to a timing attack whether the strings are the same length. """

    try:
        s1 = unicodedata.normalize('NFKC', str(s1))
        s2 = unicodedata.normalize('NFKC', str(s2))
    except:
        s1 = unicodedata.normalize('NFKC', unicode(s1))
        s2 = unicodedata.normalize('NFKC', unicode(s2))
    return compare_digest(s1, s2)