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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 to_modify(self, uid):
        '''
        Try to edit the link.
        '''
        if self.userinfo.role[1] >= '3':
            pass
        else:
            return False

        self.render('misc/link/link_edit.html',
                    kwd={},
                    postinfo=MLink.get_by_uid(uid),
                    userinfo=self.userinfo)