You're suggesting to people that they should buy research use only chemicals and attempt to compound them at home? That is incredibly irresponsible and dangerous.
There's a certain 'techbio' startup that also has this same requirement. Judging by how long their positions tend to be open for, I would anecdotally say it's not a winning strategy.
FDA approval makes it considerably easier, and in many cases possible at all, to get reimbursement for these tests. I work in the field and this is a constant hurdle to overcome.
As someone in the field, I can say with certainty to expect FDA approved liquid biopsy tests (for somatic variants) to start appearing on market in the next year, if not sooner.
I'll also point out that detecting germline variants (which is what Invitae is doing) is considerably easier than somatic variants, which is what tests ala Grail and PGDx do. Of course this doesn't discount the work of Invitae, absolutely sound tech behind it.
I'll admit I may have missed it in my quick scroll through, but I don't see iterators (as a concept) or generators anywhere. I guess you could argue the latter are too advanced, but I'd argue both are central to proper python.
Edit: clearly I'm illiterate, a closer inspection shows iteration brought up several times.