fix the flask example. #895
fix the flask example. #895

tobias47n9e/social-core,python-social-auth/social-core,cjltsod/python-social-auth,cjltsod/python-social-auth,rsalmaso/python-social-auth,python-social-auth/social-storage-sqlalchemy,python-social-auth/social-app-cherrypy,python-social-auth/social-app-django,rsalmaso/python-social-auth,python-social-auth/social-app-django,fearlessspider/python-social-auth,python-social-auth/social-app-django,fearlessspider/python-social-auth,python-social-auth/social-docs,python-social-auth/social-core,fearlessspider/python-social-auth