Change signature to attrgettuple(names).
Add asttools.iter_statements.
Add asttools.replace.  (Note implied addition to both code and test folders.
Refactor to create pending.Link_i_i.
$ git mv alib/pending.py alib/techdebt.py # And change an import also.
Refactor to create script.make_splice_node.
Add inspect to script.py that recognises exactly the same statements to change.
Part way to making script in the new way.  Tests still pass.
Create code_store the new way and use it.
Delete much now redundant code.
Fix off-by-one and now use only the new way when creating a script.
Removve much redundant (and ugly) code.
In code make explicit that signature is run_test(test_no).
Sort out interface mismatch and thus remove _WrappedEvaluator.