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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 currentItemChanged(self, _currentIndex=None, _previousIndex=None):
 """ Updates the description text widget when the user clicks on a selector in the table. The _currentIndex and _previousIndex parameters are ignored. """

        self.editor.clear()
        self.editor.setTextColor(QCOLOR_REGULAR)

        regItem = self.getCurrentRegItem()

        if regItem is None:
            return

        if self._importOnSelect and regItem.successfullyImported is None:
            self.importRegItem(regItem)

        if regItem.successfullyImported is None:
            self.editor.setTextColor(QCOLOR_NOT_IMPORTED)
            self.editor.setPlainText('<plugin not yet imported>')
        elif regItem.successfullyImported is False:
            self.editor.setTextColor(QCOLOR_ERROR)
            self.editor.setPlainText(str(regItem.exception))
        elif regItem.descriptionHtml:
            self.editor.setHtml(regItem.descriptionHtml)
        else:
            self.editor.setPlainText(regItem.docString)