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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 cursor_position_changed(self):
 """Used to detect when cursor change position and to auto select word underneath it"""

        log.debug("cursor_position_changed")

        cur = self.textCursor()
        log.debug(cur.position())
        log.debug(cur.selectedText())
        if len(cur.selectedText()) == 0:
            cur.select(QtGui.QTextCursor.WordUnderCursor)
            self.setTextCursor(cur)