tuples = [(1, 4), (2, 5), (3, 6), (1, 6), (0, 7), (3, 7), (0, 8), (2, 8), (5, 9), (4, 9)]

starting_tuple = [e for e in tuples if e[0] == 0][0]
## note: 'starting_tuple' could be either (0, 7) or (0, 8), starting direction doesn't matter

order = [starting_tuple[0], starting_tuple[1]]
## order will always start from point 0

idx = tuples.index(starting_tuple)
## index of the starting tuple


def findNext():
    global idx
    for i, e in enumerate(tuples):
        if order[-1] in e and i != idx:
            ind = e.index(order[-1])
            c = 0 if ind == 1 else 1
            order.append(e[c])
            idx = tuples.index(e)


for i in range(len(tuples)/2):
    findNext()

print order