sorter.py

macroset = {
        "oxObjectClass": "oxPublished:4",
        "oxReserved": "oxOrgOID:0",
        "oxSyntax": "oxPublished:1",
        "oxOrgOID": "1.3.6.1.4.1.48710",
        "oxSomething": "oxAttribute:0",
        "oxThird": "oxSomething:3",
        "oxMatchRules": "oxPublished:2",
        "oxPublished": "oxOrgOID:1",
        "oxAttribute": "oxPublished:3",
}

def __compare_defs(m1, m2):
    try:
        n1 = int(m1[1].split(':')[1])
        n2 = int(m2[1].split(':')[1])
        return n1 - n2
    except IndexError:
        print "Index error"
        print m1, m2
        return 0

def sorter(macros, parent):
    #print "calling with parent {0}".format(parent)
    children = [(k, v) for k, v in macros.items() if parent in v]
    items = [parent]
    for k, v in sorted(children, cmp=__compare_defs):
        items.extend(sorter(macros, k))
    return items

print sorter(macroset, 'oxOrgOID')