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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 click(self):
 """ Pretends to user clicked it, sending the signal and everything. """

        if self.is_checkable():        
            if self.is_checked(): self.set_checked(False)
            else:                 self.set_checked(True)
            self.signal_clicked.emit(self.is_checked())
        else:
            self.signal_clicked.emit(True)
        return self