Text-based Tic Tac Toe with DRY and PEP-8
Input validation

Input validation is not really related to Tic-Tac-Toe, but is shared among all console programs. 

The code to get the correct coordinates should be moved into a function in its own file to reuse it in the future and make the tic-tac-toe script even shorter.

Names

askmove does a complete turn, so I would call it: make_turn

Refactor

The check for the winning position is very much isolated from the rest of the program. I think the program would gain a lot of readibility if you wrote a is_won function.