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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 token_auth(self, token):
 """Use an application token for authentication. :param str token: Application token retrieved from GitHub's /authorizations endpoint """

        if not token:
            return

        self.headers.update({
            'Authorization': 'token {0}'.format(token)
            })
        # Unset username/password so we stop sending them
        self.auth = None