Q:

Django Admin Choicefield Error

I'm trying to set the Gender for my Users in Admin but get the Error

Value u"[u'm']" is not a valid choice.

admin.py
class PlayerForm(forms.ModelForm):
    GENDER_CHOICES = (
        ('m', 'Male'),
        ('f', 'Female'),
    )
...
gender = forms.MultipleChoiceField(label="Gender", choices=GENDER_CHOICES)
...

class Meta:
    model = Player

class PlayerAdmin(admin.ModelAdmin):
    form = PlayerForm

admin.site.register(Player, PlayerAdmin)

models.py (Player Model)
class Player(AbstractBaseUser):
    GENDER_CHOICES = (
        ('m', 'Male'),
        ('f', 'Female'),
    )
    ...
    gender = models.CharField(max_length=1, choices=GENDER_CHOICES)
    ...

Fun fact: The form does display the correct default value from dadabase in admin.
POST Payload when trying to submit the Form:
------WebKitFormBoundary009tVyo4cRJvIAnC
Content-Disposition: form-data; name="gender"

m

Edit: Forgot to mention that the DB is Postgres 8.4 and the column in question is a
VARCHAR(1)

A:

Since you are using MultipleChoiceField:
gender = forms.MultipleChoiceField(label="Gender", choices=GENDER_CHOICES)

It's going to save gender to a "list".  Resulting in:
>>> gender = ['m']

You need to use ChoiceField which is used to select a single thing:
gender = forms.ChoiceField(label="Gender", choices=GENDER_CHOICES)

Resulting in:
>>> gender = 'm'

