How to deploy PostgresSQL python app which is hosted in google cloud?

i have problem with deploying python app which writes down additional info to sql database. Postgres SQL is hosted in google cloud and for connecting to it i’m using credential files and invoking it through cmd in path with stored json. File
In powershell

>>CD "path where stored"
>>cloud_sql_proxy -credential_file=./delivery-302112-20b374282d35.json -instances="delivery-302112:us-central1:db=tcp:5435"

The question, how i will deploy it google app engine, And how can i call function with json. without typing it into cmd?

Source: Python Questions