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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 get_value(self, default=None):
 """Get selection from widget. Parameters default : str str for use by widget Returns ------- str selected item from the combobox """

        if default is None:
            default = ''

        try:
            text = self.currentText()

        except ValueError:
            lg.debug('Cannot convert "' + str(text) + '" to list. ' +
                     'Using default ' + str(default))
            text = default
            self.set_value(text)

        return text