Python Django ValueError:&x27；数据声明中懒洋洋地引用了……'；更改型号名称时

这是我创建的第一个模型

class IPAddresses(models.Model):
    '''
    @brief      Class for ip addresses.
    @attrs      name        Can be company name
    '''

    ip = models.GenericIPAddressField()
    name = models.CharField(max_length=150, null=True, blank=True)
    active = models.BooleanField(default=True)

    def __unicode__(self):
        return self.ip



class Authentication(models.Model):
    '''
    @brief      Custom Authentication for dashboard
    @attrs      name    can be a name of a person
    '''


    name = models.CharField(max_length=100, null=True, blank=True)
    password = models.CharField(max_length=200, unique=True)
    ip = models.ManyToManyField(IPAddresses, blank=True)

但是，我将'IPAddress'的型号名称更改为'IPAddress'，并运行了migrate。这很好，但是我的下一次迁移没有，并且一直收到此值错误：

  Apply all migrations: admin, auth, cache_admin, contenttypes, core, provider, saba_dashboard, sessions
Traceback (most recent call last):
  File "manage.py", line 22, in <module>
    execute_from_command_line(sys.argv)
  File "/Users/deanchristianarmada/Desktop/projects/asian_gaming/radar/lib/python2.7/site-packages/django/core/management/__init__.py", line 367, in execute_from_command_line
    utility.execute()
  File "/Users/deanchristianarmada/Desktop/projects/asian_gaming/radar/lib/python2.7/site-packages/django/core/management/__init__.py", line 359, in execute
    self.fetch_command(subcommand).run_from_argv(self.argv)
  File "/Users/deanchristianarmada/Desktop/projects/asian_gaming/radar/lib/python2.7/site-packages/django/core/management/base.py", line 294, in run_from_argv
    self.execute(*args, **cmd_options)
  File "/Users/deanchristianarmada/Desktop/projects/asian_gaming/radar/lib/python2.7/site-packages/django/core/management/base.py", line 345, in execute
    output = self.handle(*args, **options)
  File "/Users/deanchristianarmada/Desktop/projects/asian_gaming/radar/lib/python2.7/site-packages/django/core/management/commands/migrate.py", line 164, in handle
    pre_migrate_apps = pre_migrate_state.apps
  File "/Users/deanchristianarmada/Desktop/projects/asian_gaming/radar/lib/python2.7/site-packages/django/utils/functional.py", line 35, in __get__
    res = instance.__dict__[self.name] = self.func(instance)
  File "/Users/deanchristianarmada/Desktop/projects/asian_gaming/radar/lib/python2.7/site-packages/django/db/migrations/state.py", line 176, in apps
    return StateApps(self.real_apps, self.models)
  File "/Users/deanchristianarmada/Desktop/projects/asian_gaming/radar/lib/python2.7/site-packages/django/db/migrations/state.py", line 249, in __init__
    raise ValueError("\n".join(error.msg for error in errors))
ValueError: The field saba_dashboard.Authentication.ip was declared with a lazy reference to 'core.ipaddresses', but app 'core' doesn't provide model 'ipaddresses'.
The field saba_dashboard.Authentication_ip.ipaddresses was declared with a lazy reference to 'core.ipaddresses', but app 'core' doesn't provide model 'ipaddresses'.

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解决方案是访问数据库中的django_migrations表，并删除导致此错误的迁移。然后转到您的特定应用程序迁移文件夹并删除特定迁移

如果需要，这是最后一个选项

---

/manage.py migrate specific_app

不起作用，这是django 1.10版中的一个常见问题我自己也遇到了这样的死锁，不断得到“ValueError:field…是用对“…”的惰性引用声明的，但app“…”不提供模型“…”

在深入pgadmin并删除/恢复一些表之后，我实际上发现，通过添加一个新的迁移，告诉django所引用的模型已经更改，也可以解决这个问题：

    migrations.AlterField(
        model_name='...',
        name='...',
        field=models.ForeignKey(null=True, on_delete=django.db.models.deletion.SET_NULL, related_name='...', to='<app>.<new-model>'), <===
    ),

migrations.AlterField(
模型名称='…'，
名称=“…”，
field=models.ForeignKey（null=True，on_delete=django.db.models.deletation.SET_null，related_name='…'，to='.'），这个问题由django 1.11解决（或者至少对我来说是这样）
我的问题是PyCharm的重构变得有点激进，并更改了实际迁移文件中的模型引用。还原了更改的迁移并能够继续

如果这有助于任何人使用Django的更新版本，该版本通常可以处理模型重命名而不会出现问题。
这应该是可以接受的答案，因为它暴露了根本原因：缺少依赖项。
    migrations.AlterField(
        model_name='...',
        name='...',
        field=models.ForeignKey(null=True, on_delete=django.db.models.deletion.SET_NULL, related_name='...', to='<app>.<new-model>'), <===
    ),