Am trying to pre-select a radio button created with the django.forms library :

    choices = forms.ChoiceField(
        widget = forms.RadioSelect(),
        choices = [
            ['a', 'i liked it'],
            ['b', 'i did not like it']
        ],
        required=True
    )

How would I go about getting the 'a' choice pre-selected on a freshly loaded unbound form ?