RTFM!
# From data-loader directory:
python3 main.py -h
# Dry run by default
time AWS_PROFILE=myprofile python3 main.py -f my-template.json -t my-table-name -n 3
# Commit true to write to ddb
time AWS_PROFILE=myprofile python3 main.py -f my-template.json -t my-table-name -n 3 --commit true