For real reproducibility you want to go a step further with a virtual machine or something. Freezing your python dependencies won't shield you from changes in y

For real reproducibility you want to go a step further with a virtual machine or something. Freezing your python dependencies won't shield you from changes in your C standard library or differences in vector extensions or whatever. In practice, most codes shouldn't be so fragile though if dependencies are reasonably well behaved... Otherwise how can you even trust that the dependency is giving a reasonable answer?