tf.eye(2)

<tf.Tensor: shape=(2, 2), dtype=float32, numpy=
array([[1., 0.],
       [0., 1.]], dtype=float32)>

tf.eye(2, batch_shape=[3])

<tf.Tensor: shape=(3, 2, 2), dtype=float32, numpy=
array([[[1., 0.],
        [0., 1.]],

       [[1., 0.],
        [0., 1.]],

       [[1., 0.],
        [0., 1.]]], dtype=float32)>

tf.eye(2, num_columns=3)

<tf.Tensor: shape=(2, 3), dtype=float32, numpy=
array([[1., 0., 0.],
       [0., 1., 0.]], dtype=float32)>