title: django migration Model has no field named True
body: <p>I have run into a migration problem. I have a simple model</p>
  
  <pre><code>class MyUser(models.Model):
        user = models.ForeignKey(settings.AUTH_USER_MODEL,null=True,blank=True)
        user_roles = ((,), (,), )
        role = models.CharField(max_length = 40, choices = user_roles)
        users_organisation = models.OneToOneField(Organisation, blank=True, null=True, on_delete = models.CASCADE)
  
   class Organisation(models.Model):
         name = models.CharField(max_length = 40, default ="name")
         address = AddressField()
  
   class User(AbstractBaseUser, PermissionsMixin):
  email = models.EmailField(unique=True, null=True)
  first_name = models.CharField(max_length = 100)
  last_name = models.CharField(max_length = 100)
  user_name = models.CharField(max_length = 100)
  
  is_staff = models.BooleanField(
      _('staff status'),
      default=False,
      help_text=_('Designates whether the user can log into this site.'),
  )
  is_active = models.BooleanField(
      _('active'),
      default=True,
      help_text=_(
          'Designates whether this user should be treated as active. '
          'Unselect this instead of deleting accounts.'
      ),
  )
  is_admin = False
  
  USERNAME_FIELD = 'email'
  objects = MyUserManager()
  
  def __str__(self):
      return self.email
  
  def get_full_name(self):
      return self.email
  
  def get_short_name(self):
      return self.email
  </code></pre>
  
  <p>These are the model. It was working fine but suddenly I did a migration and I am in trouble.</p>
  
  <pre><code>Applying app.0001_initial...Traceback (most recent call last):
  File "/home/user/.local/lib/python3.5/site-    packages/django/db/models/options.py", line 617, in get_field
  return self.fields_map[field_name]
  KeyError: True
  
  During handling of the above exception, another exception occurred:
  
  Traceback (most recent call last):
  File "manage.py", line 10, in &lt;module&gt;
  execute_from_command_line(sys.argv)
  File "/home/user/.local/lib/python3.5/site-   packages/django/core/management/__init__.py", line 367, in    execute_from_command_line
  utility.execute()
  File "/home/user/.local/lib/python3.5/site-     packages/django/core/management/__init__.py", line 359, in execute
  self.fetch_command(subcommand).run_from_argv(self.argv)
  File "/home/user/.local/lib/python3.5/site- packages/django/core/management/base.py", line 294, in run_from_argv
  self.execute(*args, **cmd_options)
  File "/home/user/.local/lib/python3.5/site-  packages/django/core/management/base.py", line 345, in execute
   output = self.handle(*args, **options)
   File "/home/user/.local/lib/python3.5/site-   packages/django/core/management/commands/migrate.py", line 204, in handle
  fake_initial=fake_initial,
  File "/home/user/.local/lib/python3.5/site-  packages/django/db/migrations/executor.py", line 115, in migrate
   state = self._migrate_all_forwards(state, plan, full_plan, fake=fake,   fake_initial=fake_initial)
   File "/home/user/.local/lib/python3.5/site- packages/django/db/migrations/executor.py", line 145, in  _migrate_all_forwards
   state = self.apply_migration(state, migration, fake=fake,   fake_initial=fake_initial)
  File "/home/user/.local/lib/python3.5/site- packages/django/db/migrations/executor.py", line 244, in apply_migration
  state = migration.apply(state, schema_editor)
  File "/home/user/.local/lib/python3.5/site-  packages/django/db/migrations/migration.py", line 129, in apply
  operation.database_forwards(self.app_label, schema_editor, old_state,    project_state)
   File "/home/user/.local/lib/python3.5/site-  packages/django/db/migrations/operations/models.py", line 96, in   database_forwards
  schema_editor.create_model(model)
  File "/home/user/.local/lib/python3.5/site- packages/django/db/backends/base/schema.py", line 246, in create_model
  definition, extra_params = self.column_sql(model, field)
  File "/home/user/.local/lib/python3.5/site-  packages/django/db/backends/base/schema.py", line 136, in column_sql
  db_params = field.db_parameters(connection=self.connection)
  File "/home/user/.local/lib/python3.5/site-packages/django/db/models/fields/related.py", line 940, in db_parameters
  return {"type": self.db_type(connection), "check":   self.db_check(connection)}
  File "/home/user/.local/lib/python3.5/site-packages/django/db/models/fields/related.py", line 937, in db_type
  return self.target_field.rel_db_type(connection=connection)
  File "/home/user/.local/lib/python3.5/site-packages/django/db/models/fields/related.py", line 855, in target_field
  return self.foreign_related_fields[0]
  File "/home/user/.local/lib/python3.5/site-packages/django/db/models/fields/related.py", line 595, in foreign_related_fields
  return tuple(rhs_field for lhs_field, rhs_field in self.related_fields if rhs_field)
  File "/home/user/.local/lib/python3.5/site-packages/django/db/models/fields/related.py", line 582, in related_fields
  self._related_fields = self.resolve_related_fields()
  File "/home/user/.local/lib/python3.5/site-packages/django/db/models/fields/related.py", line 575, in resolve_related_fields
  else self.remote_field.model._meta.get_field(to_field_name))
  File "/home/user/.local/lib/python3.5/site-packages/django/db/models/options.py", line 619, in get_field
  raise FieldDoesNotExist('%s has no field named %r' %   (self.object_name, field_name))
  django.core.exceptions.FieldDoesNotExist: MyUser has no field named  True
  </code></pre>
  
  <p>This happens when I run manage.py migrate. I have tried to reset the migrations => delete all migrations, re-create database and makemigrations >> migrate but I still get to the same problem. It is hard for me to debug this as all the errors are happening inside the migration code.</p>
  
  <p>Will be appreciative if atleast some one can give me an a way to debug and solve the issue.</p>
  
  <p>Edited. This problem was caused by an un related model pointing to MyUser.
  stripped down version.</p>
  
  <pre><code>class OtherModel(models.Model):
      ....
      ....
      ....
      created_by = models.ForeignKey('MyUser', blank = True, null = True, on_delete = True)
  </code></pre>