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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 getFileHandle(self, dataFile, openMethod):
 """ Returns handle associated to the filename. If the file is already opened, update its priority in the cache and return its handle. Otherwise, open the file using openMethod, store it in the cache and return the corresponding handle. """

        if dataFile in self._memoTable:
            handle = self._memoTable[dataFile]
            self._update(dataFile, handle)
            return handle
        else:
            try:
                handle = openMethod(dataFile)
            except ValueError:
                raise exceptions.FileOpenFailedException(dataFile)

            self._memoTable[dataFile] = handle
            self._add(dataFile, handle)
            if len(self._memoTable) > self._maxCacheSize:
                dataFile = self._removeLru()
                del self._memoTable[dataFile]
            return handle