Create a new L{Person} with the given C{nickname}.

        @type nickname: C{unicode}
        @param nickname: The value for the I{name} attribute of the created
            L{Person}.

        @raise L{liveform.InputError}: When some aspect of person creation
        raises a L{ValueError}.

def addPerson(self, nickname):
        """
        Create a new L{Person} with the given C{nickname}.

        @type nickname: C{unicode}
        @param nickname: The value for the I{name} attribute of the created
            L{Person}.

        @raise L{liveform.InputError}: When some aspect of person creation
        raises a L{ValueError}.
        """
        try:
            self.organizer.createPerson(nickname)
        except ValueError, e:
            raise liveform.InputError(unicode(e))