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

Given a string expression representing arbitrarily nested ternary expressions, evaluate the expression, and return the result of it.
You can always assume that the given expression is valid and only contains digits, '?', ':', 'T', and 'F' where 'T' is true and 'F' is false. All the numbers in the expression are one-digit numbers (i.e., in the range [0, 9]).
The conditional expressions group right-to-left (as usual in most languages), and the result of the expression will always evaluate to either a digit, 'T' or 'F'.
 
Please complete the following python code precisely:
```python
class Solution:
    def parseTernary(self, expression: str) -> str:
```