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[sgbaird]

Address feedback from AccelerationConsortium/ac-microcourses#221 (reply in thread)

at the time I was under the impression that payload is just the document with 'sensor_data' as added keys

There should be another line on insert.py that instructs us to put that document on a separate payload, or just something that indicates the document is part of the payload and use that function on mongo_db_credentials_test.py to upload to the database

I think the last TODO on insert.py has a lot more steps involved