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

You are given a string time in the form of  hh:mm, where some of the digits in the string are hidden (represented by ?).
The valid times are those inclusively between 00:00 and 23:59.
Return the latest valid time you can get from time by replacing the hidden digits.
 
Please complete the following python code precisely:
```python
class Solution:
    def maximumTime(self, time: str) -> str:
```