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

You are given an array of binary strings strs and two integers m and n.
Return the size of the largest subset of strs such that there are at most m 0's and n 1's in the subset.
A set x is a subset of a set y if all elements of x are also elements of y.
 
Please complete the following python code precisely:
```python
class Solution:
    def findMaxForm(self, strs: List[str], m: int, n: int) -> int:
```