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

You are given an integer array arr.
We split arr into some number of chunks (i.e., partitions), and individually sort each chunk. After concatenating them, the result should equal the sorted array.
Return the largest number of chunks we can make to sort the array.
 
Please complete the following python code precisely:
```python
class Solution:
    def maxChunksToSorted(self, arr: List[int]) -> int:
```