There are two flags that may be used for test, should_include_non_live and is_test_device:true.
What are the differences between them?
should_include_non_live is explained here: https://developer.amazon.com/public/solutions/devices/dash-replenishment-service/docs/dash-lwa-web-api
is_test_device is described here: https://developer.amazon.com/public/solutions/devices/dash-replenishment-service/docs/dash-test-device-purchases
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