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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 checkAlphabet(self, count=10):
 """ A function which checks if an AA read really contains amino acids. This additional testing is needed, because the letters in the DNA alphabet are also in the AA alphabet. @param count: An C{int}, indicating how many bases or amino acids at the start of the sequence should be considered. If C{None}, all bases are checked. @return: C{True} if the alphabet characters in the first C{count} positions of sequence is a subset of the allowed alphabet for this read class, or if the read class has a C{None} alphabet. @raise ValueError: If a DNA sequence has been passed to AARead(). """

        if six.PY3:
            readLetters = super().checkAlphabet(count)
        else:
            readLetters = Read.checkAlphabet(self, count)
        if len(self) > 10 and readLetters.issubset(set('ACGT')):
            raise ValueError('It looks like a DNA sequence has been passed to '
                             'AARead().')
        return readLetters