code: def clear(self):
          '''Clear the container from all data.'''
          self._size = 0
          self._level = 1
          self._head = Node('HEAD', None,
                            [None]*SKIPLIST_MAXLEVEL,
                            [1]*SKIPLIST_MAXLEVELf clear(self):
          '''Clear the container from all data.'''
          self._size = 0
          self._level = 1
          self._head = Node('HEAD', None,
                            [None]*SKIPLIST_MAXLEVEL,
                            [1]*SKIPLIST_MAXLEVEL)
docs: Clear the container from all data.