这是我的代码：

class ChangeOfficialForm(Form):
    is_official = SelectField(
        'Officially Approved',choices=[(True,'Yes'),(False,'No')],validators=[Datarequired()],coerce=bool
    )
    submit = SubmitField('Update status')

出于某种原因,is_official.data始终为True.我怀疑我误解了胁迫是如何起作用的.