我需要一个序列化器，在那里我可以用path_to_file获取我的文件版本，如

{
   1:path_to_file,
   2: path_to_file,
   .... : ..........,
   n_verison: path_to_file
}

models.py

class Report(models.Model):
    
    employee = models.ForeignKey(Worker, on_delete=models.SET_NULL, null=True)
    file_name = models.CharField(max_length=20, null=True)
    datetime = models.DateTimeField(auto_created=True)
    
class ReportVersionInfo(models.Model):

    report = models.ForeignKey(Report, on_delete=models.CASCADE)
    version = models.IntegerField()
    file = models.FileField()

    
    def save(self, *args, **kwargs):
        # This means that the model isn't saved to the database yet
        if self._state.adding:
            # Get the maximum display_id value from the database
            last_id = self.objects.all().aggregate(largest=models.Max('version'))['largest']

            # aggregate can return None! Check it first.
            # If it isn't none, just use the last ID specified (which should be the greatest) and add one to it
            if last_id is not None:
                self.version = last_id + 1

serializer.py

from rest_framework import serializers
from django.utils import timezone

from worker.models import Worker
from report import models

class FileVersionSerializer(serializers.ModelSerializer):

    class Meta: 
        model = models.ReportVersionInfo
        fields = ['version', 'file']
        read_only_fields = ['version']
    

class ReportsSerializers(serializers.ModelSerializer):
    
    report_file = serializers.SerializerMethodField()
    class Meta: 
        
        model = models.Report
        fields = ['employee','file_name', 'report_file',]

views.py

class ReportsViewSet(viewsets.ModelViewSet):
    
    queryset = models.Report.objects.all()
    serializer_class = serializers.ReportsSerializers

我是使用drf的新手，所以我道歉，如果你认为这是一个愚蠢的问题，我尝试了所有的例子或任何serializermethods，阅读文档，并没有找到任何可以帮助我与此