Sanity check that .csv can be written to prior to execution

[Cooper-Kunz]

Issue

Currently you can run the tool without a valid place to store output and if an error occurs while executing, valuable data is lost.

Potential solutions

Need to check, and perhaps modify the algorithm so that data is appended to the .csv file as accounts are created in case a crash happens (in which case the generated scenario may still have some utility, even though it didn't full execute successfully).

Questions

What's the best way to manage & ensure valuable data isn't entirely lost in the event of a failure?