code: def get_children_of(self, component, kind=None):
          
  
          structure, trace, item = self._get_structure_and_trace(component)
          item_kind, item_label = item.split(':')
  
          if isinstance(kind, str):
              kind = [kind]
  
          if item_kind not in ['orbit']:
              # return None
              return []
          else:
              items = self._get_by_trace(structure, trace[:-1]+[trace[-1]+1])
              # we want to ignore suborbits
              #return [str(ch.split(':')[-1]) for ch in items if isinstance(ch, unicode)]
              return [str(ch.split(':')[-1]) for ch in items if isinstance(ch, unicode) and (kind is None or ch.split(':')[0] in kind)]
docs: get to component labels of the children of a given component