Buggy python submission (verdict: Time Limit Exceeded):
h, w = map(int, input().split())
ch, cw = map(int, input().split())
dh, dw = map(int, input().split())
ch -= 1
cw -= 1
dh -= 1
dw -= 1
maze = [input() for _ in range(h)]
directions = [(-2, -2), (-2, -1), (-2, 0), (-2, 1), (-2, 2),
              (-1, -2), (-1, -1), (-1, 0), (-1, 1), (-1, 2),
              (0, -2),  (0, -1),           (0, 1),  (0, 2),
              (1, -2),  (1, -1),  (1, 0),  (1, 1),  (1, 2),
              (2, -2),  (2, -1),  (2, 0),  (2, 1),  (2, 2)]

INF = 10 ** 9
mp = [[INF for _ in range(w)] for _ in range(h)]
mp[ch][cw] = 0
q = [(ch, cw)]
for y, x in q:
    for dy, dx in directions:
        ny, nx = y + dy, x + dx
        if (ny < 0 or h <= ny) or (nx < 0 or w <= nx):
            continue
        if maze[ny][nx] == '#':
            continue
        is_teleported = abs(dy) + abs(dx) > 1
        cost = mp[y][x] + is_teleported
        if mp[ny][nx] > cost:
            mp[ny][nx] = cost
            q.append((ny, nx))

if mp[dh][dw] == INF:
    print(-1)
else:
    print(mp[dh][dw])

Fixed submission:
h, w = map(int, input().split())
ch, cw = map(int, input().split())
dh, dw = map(int, input().split())
ch -= 1
cw -= 1
dh -= 1
dw -= 1
maze = [input() for _ in range(h)]
walk = [(-1, 0),  (1, 0), (0, -1), (0, 1)]
teleport = [(-2, -2), (-2, -1), (-2, 0), (-2, 1), (-2, 2),
            (-1, -2), (-1, -1),          (-1, 1), (-1, 2),
            (0, -2),                              (0, 2),
            (1, -2),  (1, -1),           (1, 1),  (1, 2),
            (2, -2),  (2, -1),  (2, 0),  (2, 1),  (2, 2)]

INF = 10 ** 9
mp = [[INF for _ in range(w)] for _ in range(h)]
mp[ch][cw] = 0
walkable = [(ch, cw)]
while True:
    for y, x in walkable:
        for dy, dx in walk:
            ny, nx = y + dy, x + dx
            if (ny < 0 or h <= ny) or (nx < 0 or w <= nx):
                continue
            if maze[ny][nx] == '#':
                continue
            if mp[ny][nx] != INF:
                continue
            mp[ny][nx] = mp[y][x]
            walkable.append((ny, nx))

    teleportable = []
    for y, x in walkable:
        for dy, dx in teleport:
            ny, nx = y + dy, x + dx
            if (ny < 0 or h <= ny) or (nx < 0 or w <= nx):
                continue
            if maze[ny][nx] == '#':
                continue
            if mp[ny][nx] != INF:
                continue
            mp[ny][nx] = mp[y][x] + 1
            teleportable.append((ny, nx))

    if mp[dh][dw] != INF:
        print(mp[dh][dw])
        break
    if teleportable == []:
        print(-1)
        break
    walkable = teleportable

Buggy python submission (verdict: Time Limit Exceeded):
h, w = map(int, input().split())
ch, cw = map(int, input().split())
dh, dw = map(int, input().split())
ch -= 1
cw -= 1
dh -= 1
dw -= 1
maze = [input() for _ in range(h)]
directions = [(-2, -2), (-2, -1), (-2, 0), (-2, 1), (-2, 2),
              (-1, -2), (-1, -1), (-1, 0), (-1, 1), (-1, 2),
              (0, -2),  (0, -1),           (0, 1),  (0, 2),
              (1, -2),  (1, -1),  (1, 0),  (1, 1),  (1, 2),
              (2, -2),  (2, -1),  (2, 0),  (2, 1),  (2, 2)]

INF = 10 ** 9
mp = [[INF for _ in range(w)] for _ in range(h)]
mp[ch][cw] = 0
q = [(ch, cw)]
for y, x in q:
    for dy, dx in directions:
        ny, nx = y + dy, x + dx
        if (ny < 0 or h <= ny) or (nx < 0 or w <= nx):
            continue
        if maze[ny][nx] == '#':
            continue
        is_teleported = abs(dy) + abs(dx) > 1
        cost = mp[y][x] + is_teleported
        if mp[ny][nx] > cost:
            mp[ny][nx] = cost
            q.append((ny, nx))

if mp[dh][dw] == INF:
    print(-1)
else:
    print(mp[dh][dw])

Fixed submission:
h, w = map(int, input().split())
ch, cw = map(int, input().split())
dh, dw = map(int, input().split())
ch -= 1
cw -= 1
dh -= 1
dw -= 1
maze = [input() for _ in range(h)]
walk = [(-1, 0),  (1, 0), (0, -1), (0, 1)]
teleport = [(-2, -2), (-2, -1), (-2, 0), (-2, 1), (-2, 2),
            (-1, -2), (-1, -1),          (-1, 1), (-1, 2),
            (0, -2),                              (0, 2),
            (1, -2),  (1, -1),           (1, 1),  (1, 2),
            (2, -2),  (2, -1),  (2, 0),  (2, 1),  (2, 2)]

INF = 10 ** 9
mp = [[INF for _ in range(w)] for _ in range(h)]
mp[ch][cw] = 0
walkable = [(ch, cw)]
while True:
    for y, x in walkable:
        for dy, dx in walk:
            ny, nx = y + dy, x + dx
            if (ny < 0 or h <= ny) or (nx < 0 or w <= nx):
                continue
            if maze[ny][nx] == '#':
                continue
            if mp[ny][nx] != INF:
                continue
            mp[ny][nx] = mp[y][x]
            walkable.append((ny, nx))

    teleportable = []
    for y, x in walkable:
        for dy, dx in teleport:
            ny, nx = y + dy, x + dx
            if (ny < 0 or h <= ny) or (nx < 0 or w <= nx):
                continue
            if maze[ny][nx] == '#':
                continue
            if mp[ny][nx] != INF:
                continue
            mp[ny][nx] = mp[y][x] + 1
            teleportable.append((ny, nx))

    if mp[dh][dw] != INF:
        print(mp[dh][dw])
        break
    if teleportable == []:
        print(-1)
        break
    walkable = teleportable