Dear all, I found it difficult to implement this function written in tensorflow, anyone helps me ?

```
def upscale2d(x, n):
"""Box upscaling (also called nearest neighbors).
Args:
x: 4D tensor in NHWC format.
n: integer scale (must be a power of 2).
Returns:
4D tensor up scaled by a factor n.
"""
if n == 1:
return x
return tf.batch_to_space(tf.tile(x, [n**2, 1, 1, 1]), [[0, 0], [0, 0]], n)
```