my goal is to create a custom user model in Django 1.5

```python
# myapp.models.py 
from django.contrib.auth.models import AbstractBaseUser

class MyUser(AbstractBaseUser):
    email = models.EmailField(
        verbose_name='email address',
        max_length=255,
        unique=True,
        db_index=True,
    )
    first_name = models.CharField(max_length=30, blank=True)
    last_name = models.CharField(max_length=30, blank=True)
    company = models.ForeignKey('Company')
    ...

    USERNAME_FIELD = 'email'
    REQUIRED_FIELDS = ['company']

```

I can't create a super user because of the company field (models.ForeignKey('Company') (python manage.py createsuperuser).
My question:  

How can I create a super user for my application without a company.
I tried to make a custom MyUserManager without any success:

```python
class MyUserManager(BaseUserManager):
    ...

    def create_superuser(self, email, company=None, password):
        """
        Creates and saves a superuser with the given email and password.
        """
        user = self.create_user(
            email,
            password=password,
        )
        user.save(using=self._db)
        return user

```

Or do I have to create a fake company for this user?
Thank you