The newly approved Python Enhancement Proposal 751 gives Python a standard lock file format for specifying the dependencies of projects. Here’s the what, why, and when.

This, in turn, contains a directory that is your bundled application—it has an executable file to run, along with all the libraries and other supplemental files required.

The problem I've noticed is that if I append the file with each of the 100k runs (one at a time), it can happen that two threads try to save to the file at the same time and some row (s) end up empty.