The shell type used when creating a shell. The default value is SharpOffsetShellType.
 To set this property, you need to position the timeline marker to immediately before this feature. This can be accomplished using the following code: thisFeature.timelineObject.rollTo(True)
"shellFeature_var" is a variable referencing a ShellFeature object. | 
        
"shellFeature_var" is a variable referencing a ShellFeature object. |