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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 bookmarks_changed(self):

 """Bookmarks list has changed."""

        bookmarks = self.editor.get_bookmarks()
        if self.editor.bookmarks != bookmarks:
            self.editor.bookmarks = bookmarks
            self.sig_save_bookmarks.emit(self.filename, repr(bookmarks))