code: def collapse_element(cls, overlay, ranges=None, mode='data', backend=None):
          
          from .element import Element
          from .overlay import Overlay, CompositeOverlay
          unpack = False
          if not isinstance(overlay, CompositeOverlay):
              overlay = Overlay([overlay])
              unpack = True
  
          prev_ids = tuple()
          processed = defaultdict(list)
          while True:
              match = cls.strongest_match(overlay, mode, backend)
              if match is None:
                  if unpack and len(overlay) == 1:
                      return overlay.values()[0]
                  return overlay
              (_, applicable_op, (start, stop)) = match
              if isinstance(overlay, Overlay):
                  values = overlay.values()
                  sliced = Overlay(values[start:stop])
              else:
                  values = overlay.items()
                  sliced = overlay.clone(values[start:stop])
              items = sliced.traverse(lambda x: x, [Element])
              if applicable_op and all(el in processed[applicable_op] for el in items):
                  return overlay
              result = applicable_op.apply(sliced, ranges, backend)
              if applicable_op.group:
                  result = result.relabel(group=applicable_op.group)
              if isinstance(overlay, Overlay):
                  result = [result]
              else:
                  result = list(zip(sliced.keys(), [result]))
              processed[applicable_op] += [el for r in result for el in r.traverse(lambda x: x, [Element])]
              overlay = overlay.clone(values[:start]+result+values[stop:])
  
              # Guard against infinite recursion for no-ops
              spec_fn = lambda x: not isinstance(x, CompositeOverlay)
              new_ids = tuple(overlay.traverse(lambda x: id(x), [spec_fn]))
              if new_ids == prev_ids:
                  return overlay
              prev_ids = new_ids
docs: Finds any applicable compositor and applies it.