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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 trim_shared_suffix(ref, alt):
 """ Reuse the `trim_shared_prefix` function above to implement similar functionality for string suffixes. Given ref='ABC' and alt='BC', we first revese both strings: reverse_ref = 'CBA' reverse_alt = 'CB' and then the result of calling trim_shared_prefix will be: ('A', '', 'CB') We then reverse all three of the result strings to get back the shared suffix and both prefixes leading up to it: ('A', '', 'BC') """

    n_ref = len(ref)
    n_alt = len(alt)
    n_min = min(n_ref, n_alt)
    i = 0
    while i < n_min and ref[-i - 1] == alt[-i - 1]:
        i += 1

    # i is length of shared suffix.
    if i == 0:
        return (ref, alt, '')
    return (ref[:-i], alt[:-i], ref[-i:])