find all lambdas of a specific code version

When deprecating Lambda runtimes it is important to have a bird's eye view over what Lambda versions you're running.

Using the AWS CLI you can check against all Lambdas that you have in your account, assuming your role has the appropriate access.

The below will need to be rerun for each region, and if checking multiple runtimes you'd have to run it again for different versions.

Example query run against all Lambdas in us-west-2:

aws lambda \
    list-functions \
    --function-version ALL \
    --region us-west-2 \
    --output text
    --query "Functions[?Runtime=='python3.6'].FunctionArn" \
    >> matching_lambdas.txt