Python implementation of SAML2 protocol for app engine on Google cloud platform -

i tried pysaml2 , python-saml library on google cloud platform both internally using libraries using c extensions or python wrapper on c libraries incompatible app engine app engine blocks c implemented libraries in eco system. 1 has implemented saml2 protocol in appengine using python?

pysaml2 documentation suggests pure python implementation uses library pycrytodome or cryptodome need _ctype library.

below error:

file "/home/***/anaconda2/lib/python2.7/ctypes/_init_.py", line 10, in <module>    _ctypes import union, structure, array   file "/home/***/sdks/google-cloud-sdk/platform/google_appengine/google/appengine/tools/devappserver2/python/sandbox.py", line 963, in load_module    raise importerror('no module named %s' % fullname) importerror: no module named _ctypes 

please suggest other approaches if possible.

i figured out if want use c libraries in app engine environment. first of have use app engine flexible environment instead of standard environment there use custom runtime. sample yaml file posted below. 

app.yaml

runtime: custom   env: flex   api_version: 1  handlers:   - url: /.*     script: main.app  second thing need choose proper base image build , install necessary libraries. 

example dockerfile

from gcr.io/google_appengine/python-compat-multicore   run apt-get update -y   run apt-get install -y python-pip build-essential libssl-dev libffi-dev python-dev libxml2-dev libxslt1-dev xmlsec1  run apt-get install -y curl unzip   run curl https://dl.google.com/dl/cloudsdk/release/google-cloud-sdk.tar.gz > /tmp/google-cloud-sdk.tar.gz   run mkdir -p /usr/local/gcloud   run tar -c /usr/local/gcloud -xvf /tmp/google-cloud-sdk.tar.gz   run /usr/local/gcloud/google-cloud-sdk/install.sh    run curl https://storage.googleapis.com/appengine-sdks/featured/google_appengine_1.9.40.zip > /tmp/google_appengine_1.9.40.zip   run unzip /tmp/google_appengine_1.9.40.zip -d /usr/local/gae  env path $path:/usr/local/gcloud/google-cloud-sdk/bin   env path $path:/usr/local/gae/google_appengine/   copy . /app   workdir /app    env module_yaml_path app.yaml  run pip install -r requirements.txt