Djangoで初期データを投入したい

前提・実現したいこと

ポケモン図鑑のようなものを作っています。
後々Django rest frameworksでAPIを作成する予定です。
その際、初期データを

Python
1python manage.py loaddata post_initial.json

で投入したいと考えておりますが、どう改善すればよいかわからず難儀しております。
「local variable 'pk' referenced before assignment」などとありますが、どこを修正すればよいかわかりかねております。

発生している問題・エラーメッセージ

Traceback (most recent call last):
  File "C:\Users[USERNAME]\AppData\Local\Programs\Python\Python38\lib\site-packages\django\core\serializers\base.py", line 287, in deserialize_m2m_values
    for pk in field_value:
TypeError: 'int' object is not iterable

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "C:\Users[USERNAME]\AppData\Local\Programs\Python\Python38\lib\site-packages\django\core\serializers\json.py", line 69, in Deserializer
    yield from PythonDeserializer(objects, **options)
  File "C:\Users[USERNAME]\AppData\Local\Programs\Python\Python38\lib\site-packages\django\core\serializers\python.py", line 122, in Deserializer
    values = base.deserialize_m2m_values(field, field_value, using, handle_forward_references)
  File "C:\Users[USERNAME]\AppData\Local\Programs\Python\Python38\lib\site-packages\django\core\serializers\base.py", line 294, in deserialize_m2m_values
    raise M2MDeserializationError(e, pk)
UnboundLocalError: local variable 'pk' referenced before assignment

The above exception was the direct cause of the following exception:

Traceback (most recent call last):
  File "manage.py", line 21, in <module>
    main()
  File "manage.py", line 17, in main
    execute_from_command_line(sys.argv)
  File "C:\Users[USERNAME]\AppData\Local\Programs\Python\Python38\lib\site-packages\django\core\management\__init__.py", line 401, in execute_from_command_line
    utility.execute()
  File "C:\Users[USERNAME]\AppData\Local\Programs\Python\Python38\lib\site-packages\django\core\management\__init__.py", line 395, in execute
    self.fetch_command(subcommand).run_from_argv(self.argv)
  File "C:\Users[USERNAME]\AppData\Local\Programs\Python\Python38\lib\site-packages\django\core\management\base.py", line 328, in run_from_argv
    self.execute(*args, **cmd_options)
  File "C:\Users[USERNAME]\AppData\Local\Programs\Python\Python38\lib\site-packages\django\core\management\base.py", line 369, in execute
    output = self.handle(*args, **options)
  File "C:\Users[USERNAME]\AppData\Local\Programs\Python\Python38\lib\site-packages\django\core\management\commands\loaddata.py", line 72, in handle
    self.loaddata(fixture_labels)
  File "C:\Users[USERNAME]\AppData\Local\Programs\Python\Python38\lib\site-packages\django\core\management\commands\loaddata.py", line 114, in loaddata
    self.load_label(fixture_label)
  File "C:\Users[USERNAME]\AppData\Local\Programs\Python\Python38\lib\site-packages\django\core\management\commands\loaddata.py", line 172, in load_label
    for obj in objects:
  File "C:\Users[USERNAME]\AppData\Local\Programs\Python\Python38\lib\site-packages\django\core\serializers\json.py", line 73, in Deserializer
    raise DeserializationError() from exc
django.core.serializers.base.DeserializationError: Problem installing fixture 'C:\Users[USERNAME]\Documents[*****]\django_rest_framework_test\Pokedex\fixtures\post_initial.json':

該当のソースコード

model.py

from django.db import models

class Pokemon(models.Model):
    name= models.CharField(max_length=32,primary_key = True)
    type= models.ManyToManyField(
    "Type",
    )

class Type(models.Model):
    id = models.AutoField(primary_key = True)
    name=models.CharField(max_length=32)

post_initial.json

[
  {
    "model": "Pokedex.Pokemon",
    "pk": 1,
    "fields": {
      "name": "ヒトカゲ",
      "type":1
    }
  },
  {
    "model": "Pokedex.Pokemon",
    "pk": 2,
    "fields": {
      "name": "フシギダネ",
      "type":2
    }
  },
  {
    "model": "Pokedex.Pokemon",
    "pk": 3,
    "fields": {
      "name": "ゼニガメ",
      "type":3
    }
  },
  {
    "model": "Pokedex.Pokemon",
    "pk": 4,
    "fields": {
      "name": "リザードン",
      "type":[1,5]
    }
  },
  {
    "model": "Pokedex.Pokemon",
    "pk": 5,
    "fields": {
      "name": "フシギバナ",
      "type":[1,4]
    }
  },
  {
    "model": "Pokedex.Pokemon",
    "pk": 6,
    "fields": {
      "name": "カメックス",
      "type":3
    }
  },
  {
    "model": "Pokedex.Type",
    "pk": 1,
    "fields": {
      "name": "ほのお"
    }
  },
  {
    "model": "Pokedex.Type",
    "pk": 2,
    "fields": {
      "name": "くさ"
    }
  },
  {
    "model": "Pokedex.Type",
    "pk": 3,
    "fields": {
      "name": "みず"
    }
  },
  {
    "model": "Pokedex.Type",
    "pk": 4,
    "fields": {
      "name": "どく"
    }
  },
  {
    "model": "Pokedex.Type",
    "pk": 5,
    "fields": {
      "name": "ひこう"
    }
  }
]

どうぞよろしくお願いいたします。