Please solve the programming task below using a self-contained code snippet in a markdown code block.

You are given a positive integer n.
We call an integer k fair if the number of even digits in k is equal to the number of odd digits in it.
Return the smallest fair integer that is greater than or equal to n.
 
Please complete the following python code precisely:
```python
class Solution:
    def closestFair(self, n: int) -> int:
```