(self, order=None)
return list(map(default_sort_key, (self.size, members, self.rank)))
Return a canonical key that can be used for sorting.

        Ordering is based on the size and sorted elements of the partition
        and ties are broken with the rank.

        Examples
        ========

        >>> from sympy.utilities.iterables import default_sort_key
        >>> from sympy.combinatorics.partitions import Partition
        >>> from sympy.abc import x
        >>> a = Partition([[1, 2]])
        >>> b = Partition([[3, 4]])
        >>> c = Partition([[1, x]])
        >>> d = Partition([list(range(4))])
        >>> l = [d, b, a + 1, a, c]
        >>> l.sort(key=default_sort_key); l
        [{{1, 2}}, {{1}, {2}}, {{1, x}}, {{3, 4}}, {{0, 1, 2, 3}}]
Return a canonical key that can be used for sorting.
Return a canonical key that can be used for sorting .
def sort_key(self, order=None):
        """Return a canonical key that can be used for sorting.

        Ordering is based on the size and sorted elements of the partition
        and ties are broken with the rank.

        Examples
        ========

        >>> from sympy.utilities.iterables import default_sort_key
        >>> from sympy.combinatorics.partitions import Partition
        >>> from sympy.abc import x
        >>> a = Partition([[1, 2]])
        >>> b = Partition([[3, 4]])
        >>> c = Partition([[1, x]])
        >>> d = Partition([list(range(4))])
        >>> l = [d, b, a + 1, a, c]
        >>> l.sort(key=default_sort_key); l
        [{{1, 2}}, {{1}, {2}}, {{1, x}}, {{3, 4}}, {{0, 1, 2, 3}}]
        """
        if order is None:
            members = self.members
        else:
            members = tuple(sorted(self.members,
                             key=lambda w: default_sort_key(w, order)))
        return list(map(default_sort_key, (self.size, members, self.rank)))
def sort_key ( self , order = None ) : if order is None : members = self . members else : members = tuple ( sorted ( self . members , key = lambda w : default_sort_key ( w , order ) ) ) return list ( map ( default_sort_key , ( self . size , members , self . rank ) ) )