BUILTIN_SERIALIZERS is a dictionary containing 4 inital entries: "django.core.serializers.xml_serializer" for "xml",
BUILTIN_SERIALIZERS = { "xml" : "django.core.serializers.xml_serializer" , "python" : "django.core.serializers.python" , "json" : "django.core.serializers.json" , "yaml" : "django.core.serializers.pyyaml" , }