if the following are true:

• expression state at time 32 = "iterate_args"
• arguments stack at time 32 = [ [ "ES", [ "Spain", [ ] ] ], [ ] ]
• parent stack at time 32 = [ __setitem__(locations, "ES", "Spain"), [ ] ]

then parent stack at time 33 = [ __setitem__(locations, "ES", "Spain"), [ ] ]

Start from the conclusion and work back up the proof. Click the arrow to show the parents.