Python: sort list of nested lists according to two criteria

In Python, I have a nested list like the following: ``` [ [[x1,y1,z1], [['0.9', 4], [0.8, 3], [0.5, 10], [0.1, 11]], [[x2,y2,z2], [['1.0', 8], [0.8, 3], [0.2, 1], [0.1, 8]] ...] ``` So each element is in the form: ``` [[3-tuple], [[val1, occurrences_of_val1], [val2, occurrences_of_val2],...]] ``` The second nested list is already sorted by the first item (val1 > val2 > val3 ...), but I want also the 3-tuples [x,y,z] to appear sorted in descending order according to two criteria: - value of val1 (highest first) - in case of same val1, highest occurrences_of_val1 (possibly applied to val2 if the two values above are the same) How do I do this? Probably with itemgetter, but I'm not sure in this case.