'Return partition as a sorted list of lists.
Examples
>>> from sympy.combinatorics.partitions import Partition
>>> Partition([1], [2, 3]).partition
[[1], [2, 3]]'

@property
def partition(self):

    if (self._partition is None):
        self._partition = sorted([sorted(p, key=default_sort_key) for p in self.args])
    return self._partition
