arcpy.Snap_edit ERROR 000732

[GreyEvenson]

Hello,

I'm having trouble getting a simple snap function to work in a python script.  The error that I get is:

arcgisscripting.ExecuteError: Failed to execute. Parameters are not valid.
ERROR 000732: Snap Environment: Dataset C:\Users\gevenson\Desktop\geopy_test\geop.gdb\subbasin_1 EDGE '3 Meters' does not exist or is not supported
Failed to execute (Snap).

However, subbasin does, in fact, exist and I've tested that.  So does the isolated_watershed data.  Can someone tell me where I'm going wrong with the bit of code below?  Any help would be appreciated.

arcpy.Densify_edit(isolated_watershed,"DISTANCE","1 METER")
arcpy.Snap_edit(isolated_watershed,[[subbasin,"EDGE","3 METERS"]])