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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 lessThan(self, leftIndex, rightIndex):
 """ Returns true if the value of the item referred to by the given index left is less than the value of the item referred to by the given index right, otherwise returns false. """

        leftData  = self.sourceModel().data(leftIndex,  RegistryTableModel.SORT_ROLE)
        rightData = self.sourceModel().data(rightIndex, RegistryTableModel.SORT_ROLE)

        return leftData < rightData