code: def get_declared_items(self):
          
          d = self.declaration
          engine = d._d_engine
          if engine:
              layout = {}
              for k, h in engine._handlers.items():
                  # Handlers with read operations
                  if not h.read_pair:
                      continue
                  v = getattr(d, k)
                  if k in LAYOUT_KEYS:
                      layout[k] = v
                      continue
                  yield (k, v)
  
              if layout:
                  yield ('layout', layout)
docs: Get the members that were set in the enamldef block for this
          Declaration. Layout keys are grouped together until the end so as
          to avoid triggering multiple updates.
          
          Returns
          -------
          result: List of (k,v) pairs that were defined for this widget in enaml
              List of keys and values