Custom Wipes - question on insertion

I have created a new series of wipes/transitions for the Blender sequence editor, the only problem is I don’t know how to make make the script into an operation so the gui can call a wipe when you select it.

I have simply

 elif strip.type == 'WIPE':
        col = layout.column()
        col.prop(strip, "transition_type")
        col.row().prop(strip, "direction", expand=True)

I don’t know how to add my wipes to “transition_type” so I can have the menu display my different wipes.

that transition_type property is a stock prop, isn’t it? You could either create a custom one and populate your own EnumProp(?) with the default ones + custom, or redefine that property - which is unsafe and might crash blender.