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To string from list in Terraform

Sometimes, like for example when you're trying to crowbar a WAF together you want to pass a list.

Example of list 
asn_block = [
    "16276",
    "9009",
    "13213",
    "15395",
    "15510",
    "20738",
    "20860",
    "21321",
    "25369",
    "29302",
    "29550",
    "35017",
    "35662",
    "39326",
    "42831",
    "51159",
    "57230",
    "58305",
    "59764",
    "60011",
    "60068",
    "61317",
    "62217",
    "62240",
    "199883",
    "200039",
    "57773",
    "198047"]

Converting it to a List

asn_block_render = [ join(" || ", [for s in local.asn_block : format("origin.asn == %v", s)]) ]

This will now render it like the below

"origin.asn == 16276 || origin.asn == 9009 || origin.asn == 13213 || origin.asn == 15395 || origin.asn == 15510 || origin.asn == 20738 || origin.asn == 20860 || origin.asn == 21321 || origin.asn == 25369 || origin.asn == 29302 || origin.asn == 29550 || origin.asn == 35017 || origin.asn == 35662 || origin.asn == 39326 || origin.asn == 42831 || origin.asn == 51159 || origin.asn == 57230 || origin.asn == 58305 || origin.asn == 59764 || origin.asn == 60011 || origin.asn == 60068 || origin.asn == 61317 || origin.asn == 62217 || origin.asn == 62240 || origin.asn == 199883 || origin.asn == 200039 || origin.asn == 57773 || origin.asn == 198047"

However, it's still as [""] - So to consume it as a string, we call it like the below

thing = local.asn_block_render[0]
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