try brackets?

nba_tracking_data_15_16.py

@@ -66,13 +66,15 @@ class NbaTracking(datasets.GeneratorBasedBuilder):
                     "name": datasets.Value("string"),
                     "teamid": datasets.Value("int64"),
                     "abbreviation": datasets.Value("string"),
-                    "players": list({
+                    "players": [
+                        {
                         "lastname": datasets.Value("string"),
                         "firstname": datasets.Value("string"),
                         "playerid": datasets.Value("int64"),
                         "jersey": datasets.Value("string"),
                         "position": datasets.Value("string")
-                    })
+                        }
+                    ]
                 },
                 # "home": {
                 #     "name": datasets.Value("string"),