Minimum Bounding Geometry and LIST of filends

[DmitryBubnenkov]

I need to setup at Python script list of fields for processing.
There is option with name "group_field"


Here is needed string:
arcpy.MinimumBoundingGeometry_management(inFeatures, outFeatureClass,  "CONVEX_HULL", "LIST")

so after LIST I should specify the fields. But I don't know how.
I tried to do:
arcpy.MinimumBoundingGeometry_management(inFeatures, outFeatureClass,
"CONVEX_HULL", "LIST", "cModelTxtName, tSessionTime, dSessionDate, cDataFileName, cProcLevel")

But I got error:
arcgisscripting.ExecuteError: Failed to execute. Parameters are not valid.

http://resources.arcgis.com/en/help/main/10.1/index.html#//00170000003q000000