arcpy.env.workspace = r'Database Connections\adminCon.sde'
    arcpy.MakeFeatureLayer_management(r'Database Connections\adminCon.sde\GISADMIN.Buildings', 'fl')
    arcpy.ChangeVersion_management('fl', "TRANSACTIONAL", "GISADMIN.Oli")
    arcpy.ChangeVersion_management('fl', "TRANSACTIONAL", "sde.DEFAULT")

For further information check:

https://gis.stackexchange.com/questions/123621/how-to-get-a-search-cursor-on-a-particular-version-in-arcpy