Nested lists or tuples with equal-lengths can be converted into multidimensional arrays:
>>> l = [[1,2,3],[4,5,6],[7,8,9]]
>>> a = np.array(l)
>>> a
array([[1, 2, 3],
[4, 5, 6],
[7, 8, 9]])
>>> lt = ([21,3,9,-4],[11,-3,6,-2],[-77,83,44,9])
>>> a = np.array(lt)
>>> a.ndim
2
>>> a.shape
(3, 4)
>>>
the dimension of the array
the shape of the array