old_contents: from django.db.models.query import QuerySet
  from django.utils import six, timezone
  from django.utils.encoding import force_text
  from django.utils.functional import Promise
  import datetime
  import decimal
  import json
  import uuid
  
  
  class JSONEncoder(json.JSONEncoder):
      """
      JSONEncoder subclass that knows how to encode date/time/timedelta,
      decimal types, generators and other basic python objects.
  
      Taken from https://github.com/tomchristie/django-rest-framework/blob/master/rest_framework/utils/encoders.py
      """
      def default(self, obj):  # noqa
          # For Date Time string spec, see ECMA 262
          # http://ecma-international.org/ecma-262/5.1/#sec-15.9.1.15
          if isinstance(obj, Promise):
              return force_text(obj)
          elif isinstance(obj, datetime.datetime):
              representation = obj.isoformat()
              if obj.microsecond:
                  representation = representation[:23] + representation[26:]
              if representation.endswith('+00:00'):
                  representation = representation[:-6] + 'Z'
              return representation
          elif isinstance(obj, datetime.date):
              return obj.isoformat()
          elif isinstance(obj, datetime.time):
              if timezone and timezone.is_aware(obj):
                  raise ValueError("JSON can't represent timezone-aware times.")
              representation = obj.isoformat()
              if obj.microsecond:
                  representation = representation[:12]
              return representation
          elif isinstance(obj, datetime.timedelta):
              return six.text_type(obj.total_seconds())
          elif isinstance(obj, decimal.Decimal):
              # Serializers will coerce decimals to strings by default.
              return float(obj)
          elif isinstance(obj, uuid.UUID):
              return six.text_type(obj)
          elif isinstance(obj, QuerySet):
              return tuple(obj)
          elif hasattr(obj, 'tolist'):
              # Numpy arrays and array scalars.
              return obj.tolist()
          elif hasattr(obj, '__getitem__'):
              try:
                  return dict(obj)
              except:
                  pass
          elif hasattr(obj, '__iter__'):
              return tuple(item for item in obj)
          return super(JSONEncoder, self).default(obj)
  
new_contents: from django.db.models.query import QuerySet
  from django.utils import six, timezone
  from django.utils.encoding import force_text
  from django.utils.functional import Promise
  import datetime
  import decimal
  import json
  import uuid
  
  
  class JSONEncoder(json.JSONEncoder):
      """
      JSONEncoder subclass that knows how to encode date/time/timedelta,
      decimal types, generators and other basic python objects.
  
      Taken from https://github.com/tomchristie/django-rest-framework/blob/master/rest_framework/utils/encoders.py
      """
      def default(self, obj):  # noqa
          # For Date Time string spec, see ECMA 262
          # https://ecma-international.org/ecma-262/5.1/#sec-15.9.1.15
          if isinstance(obj, Promise):
              return force_text(obj)
          elif isinstance(obj, datetime.datetime):
              representation = obj.isoformat()
              if representation.endswith('+00:00'):
                  representation = representation[:-6] + 'Z'
              return representation
          elif isinstance(obj, datetime.date):
              return obj.isoformat()
          elif isinstance(obj, datetime.time):
              if timezone and timezone.is_aware(obj):
                  raise ValueError("JSON can't represent timezone-aware times.")
              representation = obj.isoformat()
              return representation
          elif isinstance(obj, datetime.timedelta):
              return six.text_type(obj.total_seconds())
          elif isinstance(obj, decimal.Decimal):
              # Serializers will coerce decimals to strings by default.
              return float(obj)
          elif isinstance(obj, uuid.UUID):
              return six.text_type(obj)
          elif isinstance(obj, QuerySet):
              return tuple(obj)
          elif isinstance(obj, six.binary_type):
              # Best-effort for binary blobs. See #4187.
              return obj.decode('utf-8')
          elif hasattr(obj, 'tolist'):
              # Numpy arrays and array scalars.
              return obj.tolist()
          elif hasattr(obj, '__getitem__'):
              try:
                  return dict(obj)
              except Exception:
                  pass
          elif hasattr(obj, '__iter__'):
              return tuple(item for item in obj)
          return super(JSONEncoder, self).default(obj)
  
subject: Update JSONEncoder from DRF