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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 on_lstClassifications_itemSelectionChanged(self):
 """Update classification description label and unlock the Next button. .. note:: This is an automatic Qt slot executed when the field selection changes. """

        self.clear_further_steps()
        classification = self.selected_classification()
        # Exit if no selection
        if not classification:
            return
        # Set description label
        self.lblDescribeClassification.setText(classification["description"])
        # Enable the next button
        self.parent.pbnNext.setEnabled(True)