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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 _isProtein(self):
 """ check if blockSizes and scores are in the protein space or not """

        last = self.blockCount - 1
        return ((self.tEnd == self.tStarts[last] + 3 * self.blockSizes[last]) \
                and self.strand == "+") or \
                ((self.tStart == self.tSize - (self.tStarts[last] + 3 * self.blockSizes[last])\
                and self.strand == "-"))