def validate_business(form, field):
    """Valiates a PayPal business string.

    It can either be an email address or a paypal business account ID.
    """
    if not is_valid_mail(field.data, multi=False) and not re.match(r'^[a-zA-Z0-9]{13}$', field.data):
        raise ValidationError(_('Invalid email address / paypal ID'))
def validate_business ( form , field ) : if not is_valid_mail ( field . data , multi = False ) and not re . match ( r'^[a-zA-Z0-9]{13}$' , field . data ) : raise ValidationError ( _ ( 'Invalid email address / paypal ID' ) )
Valiates a PayPal business string.

    It can either be an email address or a paypal business account ID.