def METHOD_NAME(self):
    organizations = self.cleaned_data.get('organizations') or []
    max_orgs = settings.DMOJ_USER_MAX_ORGANIZATION_COUNT
    if len(organizations) > max_orgs:
        raise forms.ValidationError(ngettext('You may not be part of more than {count} public organization.',
                                             'You may not be part of more than {count} public organizations.',
                                             max_orgs).format(count=max_orgs))
    return self.cleaned_data['organizations']