code: def remove(self, slide_layout):
          
          # ---raise if layout is in use---
          if slide_layout.used_by_slides:
              raise ValueError('cannot remove slide-layout in use by one or more slides')
  
          # ---target layout is identified by its index in this collection---
          target_idx = self.index(slide_layout)
  
          # --remove layout from p:sldLayoutIds of its master
          # --this stops layout from showing up, but doesn't remove it from package
          target_sldLayoutId = self._sldLayoutIdLst.sldLayoutId_lst[target_idx]
          self._sldLayoutIdLst.remove(target_sldLayoutId)
  
          # --drop relationship from master to layout
          # --this removes layout from package, along with everything (only) it refers to,
          # --including images (not used elsewhere) and hyperlinks
          slide_layout.slide_master.part.drop_rel(target_sldLayoutId.rId)
docs: Remove *slide_layout* from the collection.
  
          Raises ValueError when *slide_layout* is in use; a slide layout which is the
          basis for one or more slides cannot be removed.