code: def make_empty(self, axes=None):
          
          if axes is None:
              axes = [ensure_index([])] + [ensure_index(a)
                                           for a in self.axes[1:]]
  
          # preserve dtype if possible
          if self.ndim == 1:
              blocks = np.array([], dtype=self.array_dtype)
          else:
              blocks = []
          return self.__class__(blocks, axes)
docs: return an empty BlockManager with the items axis of len 0