def findLongestChain(self, pairs):
cur, res = float('inf'), 0
for p in sorted(pairs, key=lambda x: x[1]):
if cur < p[0]: cur, res = p[1], res + 1
return res
4Liner Python Greedy

My solution followed the same idea after got "time limit exceeded" from my initial DP solution, but yours is obviously much clearer and cleaner. Admire!
lol and found a benefit of using a bit slower language  always force you to find a better solution. If I were using C++ etc maybe the DP solution would pass with no problem and I'll satisfy with that while miss a smarter solution like this!