OpenSpiel state methods: move_number
move_number()
Returns how many moves have been made so far in the game. Simultaneous moves (where all players act at once) count as a single move. Chance transitions also count as one move. Note that game transformations are not required to preserve the move number.
Examples:
import pyspiel
game = pyspiel.load_game("tic_tac_toe")
state = game.new_initial_state()
print(state.move_number()) # Output: 0
state.apply_action(4)
print(state.move_number()) # Output: 1
state.apply_action(0)
print(state.move_number()) # Output: 2