arr_t = np.array(l_2d).T print(arr_t) print(type(arr_t)) # [[0 3] # [1 4] # [2 5]] # <class 'numpy.ndarray'> l_2d_t = np.array(l_2d).T.tolist() print(l_2d_t) print(type(l_2d_t)) # [[0, 3], [1, 4], [2, 5]] # <class 'list'>