在Python Dict中循环的单行嵌套

Question

I have two models: Sites and Regions. A Region has many Sites.

class Site(models.Model):

  name = models.CharField(max_length=200, unique=True)

class Region(models.Model):

  name = models.CharField(max_length=200, unique=True)
  sites = models.ManyToManyField('Site')

i would like to loop through the queryset so as to get a dict (which will eventually become JSON) that looks like this:

regions = [
    {
        id: 1,
        name: "Region 1",
        sites: [
            {
                id: 1,
                name: "Site 1"
            },
            {
                id: 2,
                name: "Site 2"
            }
        ]
    },{
        id: 2,
        name: "Region 2",
        sites: [
            {
                id: 3,
                name: "Site 3"
            },
            {
                id: 4,
                name: "Site 4"
            }
        ]
    },
]

The thing is, I would like to do it in one line. I feel like I'm on the right track with {Region.name : {int(Site.id) : Site.name for Site in Region.sites.all()} for Region in Region.objects.all()} but I'm having trouble nesting the loops. I feel like it should be something like the below, but this is not working:

{ 'id' : Region.id, 'name': Region.name, 'children' : { 'id': int(Site.id), 'name' : Site.name} for Site in Site.objects.all()} for Region in Region.objects.all()}

Answer 1

I didn't test it, but maybe you want something like:

regions = [dict(r.items() + [('sites', r.site_set.all().values('id', 'name'))]) for r in Record.objects.all().values('id', 'name')]

UPD. But as Brandon noted, it would be better to not use such complicated oneliners.

Answer 2

尝试这个：

{'id' : region.id, 'name': region.name, 'sites' : { 'id': int(site.id), 'name' : site.name for site in region.sites.objects.all()} for region in Region.objects.all()}