from flask_wtf import FlaskForm from wtforms import MultipleFileField, SelectField, StringField, SubmitField from wtforms.validators import DataRequired, Length class CreateCorpusForm(FlaskForm): description = StringField( 'Description', validators=[DataRequired(), Length(1, 64)] ) files = MultipleFileField('Files') title = StringField( 'Title', validators=[DataRequired(), Length(1, 32)] ) submit = SubmitField('Create corpus') ''' def validate_files(form, field): for file in form.files.getlist[field.name]: if file.mimetype '''