code: def _is_action_available_left(self, state):
          
  
          # True if any field is 0 (empty) on the left of a tile or two tiles can
          # be merged.
          for row in range(4):
              has_empty = False
              for col in range(4):
                  has_empty |= state[row, col] == 0
                  if state[row, col] != 0 and has_empty:
                      return True
                  if (state[row, col] != 0 and col > 0 and
                          state[row, col] == state[row, col - 1]):
                      return True
  
          return False
docs: Determines whether action 'Left' is available.