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

Given an integer n, return true if and only if it is an Armstrong number.
The k-digit number n is an Armstrong number if and only if the kth power of each digit sums to n.
 
Please complete the following python code precisely:
```python
class Solution:
    def isArmstrong(self, n: int) -> bool:
```