Get a service account key from Firebase->Project Overview->Project Settings->Service Accounts->Generate new private key->Generate key and save the downloaded file as ./service_account_key.json.
Google tells you: Your private key gives access to your project's Firebase services. Keep it confidential and never store it in a public repository.
This key grants admin privileges. It is a major security issue to share this file with untrusted users. From your point of view, everybody is an untrusted user except you.
https://firebase.google.com/docs/reference/admin/python
pip3 install firebase-admin
Add json to the incuded file types.
source.include_exts = py,png,jpg,kv,atlas,json
requirements = python3,kivy, firebase-admin, cachecontrol, msgpack, requests, certifi, charset-normalizer==2.1.1, idna, urllib3, google-api-core, google-auth, cachetools, pyasn1-modules, pyasn1, rsa, pyasn1, googleapis-common-protos, protobuf, google-api-python-client, google-auth-httplib2, httplib2, pyparsing, uritemplate, google-cloud-firestore, google-cloud-core, proto-plus, google-cloud-storage, google-resumable-media, google-crc32c
android.permissions = INTERNET
As of 2022/08 firebase-admin does not run on ios, the issue is ModuleNotFoundError: No module named 'mmap'.