1def merge(intervals):
2 if not intervals:
3 return []
4 intervals.sort(key=lambda x: x[0])
5 merged = [intervals[0]]
6 for i in range(1, len(intervals)):
7 curr = intervals[i]
8 last = merged[-1]
9 if curr[0] <= last[1]:
10 last[1] = max(last[1], curr[1])
11 merged.append(curr)
12 return merged