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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 set_checked(self, checked):
 """ Properly check the correct radio button. """

        if not checked:
            self.widget.clearCheck()
        else:
            #: Checked is a reference to the radio declaration
            #: so we need to get the ID of it
            rb = checked.proxy.widget
            if not rb:
                return
            self.widget.check(rb.getId())