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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 findOrDie(s):
 """ Look up an amino acid. @param s: A C{str} amino acid specifier. This may be a full name, a 3-letter abbreviation or a 1-letter abbreviation. Case is ignored. @return: An C{AminoAcid} instance, if one can be found. Else exit. """

    aa = find(s)
    if aa:
        return aa
    else:
        print('Unknown amino acid or codon: %s' % s, file=sys.stderr)
        print('Valid arguments are: %s.' % list(CODONS.keys()),
              file=sys.stderr)
        sys.exit(1)