Dear Kevin Mills, I understand your point to some degree, but could you please clarify it further by answering the following question? Which of the following expressions will be valid in your model, and as what currently valid expression will each of the valid ones evaluated? (For instance, I understand d[*(1,2,3)] will be valid and evaluated as d[1][2][3] . Some may seem redundant, but just to be sure...) (1) d[*(1,2,3), ] (2) d[*(),1,2,3,*()] (3) d[*(1,2,3),*()] (4) d[] The reason why this could clarify your point is, for example, it's tempting to possibly incorrectly assume all (1) to (3) are going to be valid and equivalent to d[*(1,2,3)] (as their counterparts are in a function call), which could be a source of confusion since some of them might be too hard to not interpret as d[1,2,3] if valid. (E.g., I happen to have recently proposed (1) to (3) and the like as valid expressions equivalent to d[1,2,3] while not giving any interpretation to d[*x] here https://mail.python.org/archives/list/python-ideas@python.org/message/BEGGQE... with a summary https://mail.python.org/archives/list/python-ideas@python.org/message/KF37FM... ) Best regards, Takuo