python - Pythonic way to parse list of dictionaries for a specific attribute? -

i want cross reference dictionary , django queryset determine elements have unique dictionary['name'] , djangomodel.name values, respectively. way i'm doing to:

• create list of dictionary['name'] values
• create list of djangomodel.name values
• generate list of unique values checking inclusion in lists

this looks follows:

alldbtests = dbp.test_set.exclude(end_date__isnull=false)   #django queryset  vctestnames = [vctest['name'] vctest in vcdict['tests']]   #from dictionary dbtestnames = [dbtest.name dbtest in alldbtests]    #from django model  # compare tests in protocol in fortytwo's db protocol vc  obsoletetests = [dbtest dbtest in alldbtests if dbtest.name not in vctestnames] newtests = [vctest vctest in vcdict if vctest['name'] not in dbtestnames] 

it feels unpythonic have generate intermediate list of names (lines 2 , 3 above), able check inclusion after. missing anything? suppose put 2 list comprehensions in 1 line this:

obsoletetests = [dbtest dbtest in alldbtests if dbtest.name not in [vctest['name'] vctest in vcdict['tests']]] 

but seems harder follow.

edit: think of initial state this:

# vcdict list of django models following true alldbtests[0].name == 'test1' alldbtests[1].name == 'test2' alldbtests[2].name == 'test4'  dict1 = {'name':'test1', 'status':'pass'} dict2 = {'name':'test2', 'status':'pass'} dict3 = {'name':'test5', 'status':'fail'}  vcdict = [dict1, dict2, dict3] 

i can't convert sets , take difference unless strip things down name string, lose access rest of model/dictionary, right? sets work here if had same type of object in both cases.

vctestnames = dict((vctest['name'], vctest) vctest in vcdict['tests']) dbtestnames = dict((dbtest.name, dbtest) dbtest in alldbtests)  obsoletetests = [vctestnames[key]                  key in set(vctestnames.keys()) - set(dbtestnames.keys())]  newtests = [dbtestnames[key]             key in set(dbtestnames.keys()) - set(vctestnames.keys())]