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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 setAnonymous(self, is_anonymous):
 """Set whether this request should be made anonymously. If a request is anonymous, the identifier will not be sent in the request. This is only useful if you are making another kind of request with an extension in this request. Anonymous requests are not allowed when the request is made with OpenID 1. @raises ValueError: when attempting to set an OpenID1 request as anonymous """

        if is_anonymous and self.message.isOpenID1():
            raise ValueError('OpenID 1 requests MUST include the '
                             'identifier in the request')
        else:
            self._anonymous = is_anonymous