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

Given an n x n array of integers matrix, return the minimum sum of any falling path through matrix.
A falling path starts at any element in the first row and chooses the element in the next row that is either directly below or diagonally left/right. Specifically, the next element from position (row, col) will be (row + 1, col - 1), (row + 1, col), or (row + 1, col + 1).
 
Please complete the following python code precisely:
```python
class Solution:
    def minFallingPathSum(self, matrix: List[List[int]]) -> int:
```