Phython3 code to find nested uniques within a JSON file - json

Question

First off I'm a scientist, NOT a coder. Haven't coded since my college days so feel free to knock me around a bit. But I have a project for a non-profit that I'd like to help with.
I have the code to dl the JSON file, a sample of which I'll provide below. But for now, my goal is to search and display unique birds in each of the unique areas. I've spend about 10 days scouring the web, writing many hundreds of lines of code, all to no avail. I'm certain one of you will spend 3 minutes to write one line comprehension that'll do it perfectly. My hat's off in advance.
Here's a small sample extracted from thousands of items in a dl'ed JSON file:
{
"speciesCode": "snogoo",
"comName": "Snow Goose",
"sciName": "Anser caerulescens",
"locId": "L1415313",
"locName": "Vacation Isle",
"obsDt": "2023-02-15 15:28",
"howMany": 3,
"lat": 32.7750146,
"lng": -117.2352583,
"obsValid": false,
"obsReviewed": false,
"locationPrivate": false,
"subId": "S128423924"
},
{
"speciesCode": "gwfgoo",
"comName": "Greater White-fronted Goose",
"sciName": "Anser albifrons",
"locId": "L1415313",
"locName": "Vacation Isle",
"obsDt": "2023-02-15 15:28",
"howMany": 1,
"lat": 32.7750146,
"lng": -117.2352583,
"obsValid": false,
"obsReviewed": false,
"locationPrivate": false,
"subId": "S128423924"
},
{
"speciesCode": "snogoo",
"comName": "Snow Goose",
"sciName": "Anser caerulescens",
"locId": "L1415313",
"locName": "Vacation Isle",
"obsDt": "2023-02-15 15:28",
"howMany": 3,
"lat": 32.7750146,
"lng": -117.2352583,
"obsValid": false,
"obsReviewed": false,
"locationPrivate": false,
"subId": "S128423922"
},
What I need to do is to extract the unique "comName" species that have been seen at each "locName". So in the above extraction there are two different records of a Snow Goose showing up at the same location. I only need one. I won't give you the giggles by offering my attempts. I can traverse the JSON fine, and create a dict with different results. But selecting the uniques in the nested loops have bamboozled me. If I've violated any common rules here, please flog me gently. I really would like to be a good netizen.
Thank you much for any help you can provide.