models.py
class Post(models.Model):
    title = models.CharField(max_length=100)
    tag = models.CharField(max_length=3)
    is_enabled = models.BooleanField(default=False)

admin.py
class PostAdmin(admin.ModelAdmin):
    list_display = ['id', 'title', 'tag', 'is_enabled']
    list_display_links = None
    readonly_fields = ['id', 'title', 'tag']

    actions = ['enable_selected', 'disable_selected']

    def enable_selected(self,requst,queryset):
        queryset.update(is_enabled=True)

    def disable_selected(self,requst,queryset):
        queryset.update(is_enabled=False)

    enable_selected.short_description = "Enable the selected Post"
    disable_selected.short_description = "Disable the selected Post"

list_display = ['is_enabled']