code: def get_child(self, name: YangIdentifier,
                    ns: YangIdentifier = None) -> Optional[SchemaNode]:
          
          ns = ns if ns else self.ns
          todo = []
          for child in self.children:
              if child.name is None:
                  todo.append(child)
              elif child.name == name and child.ns == ns:
                  return child
          for c in todo:
              grandchild = c.get_child(name, ns)
              if grandchild is not None:
                  return grandchild
docs: Return receiver's schema child.
  
          Args:
              name: Child's name.
              ns: Child's namespace (= `self.ns` if absent).