Solve the programming task below in a Python markdown code block.
Welcome. In this kata, you are asked to square every digit of a number and concatenate them.

For example, if we run 9119 through the function, 811181 will come out, because 9^(2) is 81 and 1^(2) is 1.

**Note:** The function accepts an integer and returns an integer
Also feel free to reuse/extend the following starter code:
```python
def square_digits(num):
```