def validate(self,value):
super(ChoiceField,self).validate(value)<EOL>try:<EOL><INDENT>get_template(value)<EOL><DEDENT>except TemplateDoesNotExist:<EOL><INDENT>raise ValidationError(_('<STR_LIT>' % value))<EOL><DEDENT>
Check for empty values, and for an existing template, but do not check if
this is one of the initial choices provided.