code: def dtype(self):
          
          dtypes = [space.dtype for space in self.spaces]
  
          if all(dtype == dtypes[0] for dtype in dtypes):
              return dtypes[0]
          else:
              raise AttributeError("`dtype`'s of subspaces not equal")
docs: The data type of this space.
  
          This is only well defined if all subspaces have the same dtype.
  
          Raises
          ------
          AttributeError
              If any of the subspaces does not implement `dtype` or if the dtype
              of the subspaces does not match.