In the warmup_stats code we use the API from the warmup.summary_statistics and warmup.latex modules to generate LaTeX and HTML tables. It would be preferable to use PyPy for this, If the user has it available.
From @vext01 in the #340 discussion "What may help is having the top-level warmup script invoke sub-scripts with sys.exectutable thus using the same interpreter as the top-level script did. Then it's up to the user to invoke the right interpreter. Just a thought."