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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 authenticate(self):
 """ Indicate to the client that it needs to authenticate via a 401. """

        if request.headers.get('Authorization') or request.args.get('access_token'):
            realm = 'Bearer realm="%s", error="invalid_token"' % __package__
        else:
            realm = 'Bearer realm="%s"' % __package__
        resp = Response(None, 401, {'WWW-Authenticate': realm})
        abort(401, description='Please provide proper credentials', response=resp)