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

You are given an array of strings tokens that represents an arithmetic expression in a Reverse Polish Notation.
Evaluate the expression. Return an integer that represents the value of the expression.
Note that:

The valid operators are '+', '-', '*', and '/'.
Each operand may be an integer or another expression.
The division between two integers always truncates toward zero.
There will not be any division by zero.
The input represents a valid arithmetic expression in a reverse polish notation.
The answer and all the intermediate calculations can be represented in a 32-bit integer.

 
Please complete the following python code precisely:
```python
class Solution:
    def evalRPN(self, tokens: List[str]) -> int:
```