Python Requests Demo: How to handle a web server which serves a misconfigured TLS chain

chaintest.py

import requests

# via https://whatsmychaincert.com/?webportal.stromnetz-graz.at
# "Generate the Correct Chain" + "Include Root Certificate"
# --> https://whatsmychaincert.com/generate?include_leaf=1&host=webportal.stromnetz-graz.at&submit_btn=Generate+Chain&include_root=1
CUSTOMSTORE='/tmp/webportal.stromnetz-graz.at.chained+root.crt'

print('without chain:')
try:
	requests.get('https://webportal.stromnetz-graz.at/login')
except requests.exceptions.SSLError as e:
	print('  geht nit: {}'.format(e))

print('with chain:')
r = requests.get('https://webportal.stromnetz-graz.at/login', verify=CUSTOMSTORE)

print('  geht: {}'.format(r.status_code))

output.log

% python3 certtest.py                                                 :(
without chain:
  geht nit: HTTPSConnectionPool(host='webportal.stromnetz-graz.at', port=443): Max retries exceeded with url: /login (Caused by SSLError(SSLCertVerificationError(1, '[SSL: CERTIFICATE_VERIFY_FAILED] certificate verify failed: unable to get local issuer certificate (_ssl.c:1129)')))
with chain:
  geht: 200

webportal.stromnetz-graz.at.chained+root.crt

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-----END CERTIFICATE-----
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