Question: how to change a sequence to an array?

I use convert~([points1], list) command but the outcome is not I want. The code of shortscreen is attached. I wanna change the outermost curly braces of the sequence "points1" into square brackets. Thank you all guys to answer!

The below is I want.

This is not I want cause the outermost has three square brackets! I just wanna two.

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