Question

My question is about the second break statement:
if x == xstart and y == ystart:
break

So this break statement breaks out of the while true loop correct? But then does it go back to the next closest loop (namely the while board[x][y] = OtherTile:) But because this condition is not met, it goes back to the original for xdirection, ydirection loop? I just wanted to see if my understanding was correct.

if board[xstart][ystart] not OnBoard(xstart, ystart) or board[xstart][ystart] != ' ':
    return False

#temporarily set the tile on the board, but change it back to a blank before the end of this function
board[xstart][ystart] = tile

#Set computer tile
if tile == 'X':
    OtherTile = 'O'
else:
    OtherTile = 'X'

#empty list of tiles to flip
TilesToFlip = []

#this is a for loop for two variables.  Each list of two represents a position away from the orignal spot
for xdirection, ydirection in [[1,0], [0,1], [-1,0], [0,-1], [1,-1], [1,1], [-1,1], [-1,-1]]:

    #we set x and y to the original coordinates passed to us because we want to preserve the orignal values
    x, y = xstart, ystart
    x = x + xdirection
    y = y + ydirection

    #after the first iteration, check to see if the adjacent piece is on the board and if it's the OtherTile:
    if isOnBoard(x,y) and board[x][y] == OtherTile:
        x = x + xdirection
        y = y + ydirection
        #if the next piece is not on the board, go back to the for loop to test another direction
        if not isOnBoard(x,y):
            continue
        while board[x][y] = OtherTile:
            x = x + xdirection
            y = y + ydirection
            #we break here because if we had just continued it would have gone back to the while loop.
            #since we're breaking, it goes back to the original for loop (if it goes off the board)
            if not isOnBoard(x,y):
                break

        #it finishes with the while loop if it reaches a tile that is not the OtherTile (i.e. it's blank or it's the player's)
        #so we check to see if it's the player's
        if board[x][y] == tile:
            #if it is the player's tile, then we go in the reverse direction, appending each tile to the TilesToFlip list
            while True:
                x = x - xdirection
                y = y - ydirection
                #when we reach the original tiles, we break (by then we have all the tiles that need to be flipped in store in the new list)
                if x == xstart and y == ystart:
                    break
                TilesToFlip.append([x,y])

Answer 1

It will only break the while True loop. The loop will continue forever until x == xstart and y == ystart.

Once that condition is met, it will continue on in the that outer for loop.