code: def add(self, *widgets):
          '''
          Place @widgets under the blitting hand of the Container(). Each arg 
          must be a Widget(), a fellow Container(), or an iterable. Else, things 
          get ugly...
          '''
          for w in widgets:
              if is_widget(w):
                  if w not in self.widgets:
                      self.widgets.add(w)
                      w.add_internal(self)
              elif is_container(w):
                  if w not in self.containers:
                      self.containers.add(w)
                      w.add_internal(self)
              else:
                  # If it isn't an iterable, we'll get an error here.
                  # Desired effect.
                  self.add(*wf add(self, *widgets):
          '''
          Place @widgets under the blitting hand of the Container(). Each arg 
          must be a Widget(), a fellow Container(), or an iterable. Else, things 
          get ugly...
          '''
          for w in widgets:
              if is_widget(w):
                  if w not in self.widgets:
                      self.widgets.add(w)
                      w.add_internal(self)
              elif is_container(w):
                  if w not in self.containers:
                      self.containers.add(w)
                      w.add_internal(self)
              else:
                  # If it isn't an iterable, we'll get an error here.
                  # Desired effect.
                  self.add(*w)
docs: Place @widgets under the blitting hand of the Container(). Each arg 
          must be a Widget(), a fellow Container(), or an iterable. Else, things 
          get ugly...