problem改用_id作为搜索用主键；submission更加statistic_info字段

submission/serializers.py

@@ -1,4 +1,5 @@
 from .models import Submission
+from account.models import User
 from utils.api import serializers
 from judge.languages import language_names
 
@@ -10,8 +11,13 @@ class CreateSubmissionSerializer(serializers.Serializer):
 
 
 class SubmissionModelSerializer(serializers.ModelSerializer):
+    username = serializers.SerializerMethodField()
     info = serializers.JSONField()
-    accepted_info = serializers.JSONField()
+    statistic_info = serializers.JSONField()
 
     class Meta:
         model = Submission
+
+    @staticmethod
+    def get_username(obj):
+        return User.objects.get(id=obj.user_id).username