This is my select tag in a template tag of website form in xml view

This is my class and route in my controller in my .py file

class HospitalAppointment(http.Controller):
    @http.route('/appointment_webform', type="http", auth="public", website=True)
    def patient_appointment(self, **kw):
        return http\\.request\\.render\\('hospital_management_system_n\\.create_appointment',\ \{
 \    \    \    \   \ 'patients':\\ http.request.env['hospital.patient'].search([]),
        })

    def get_patient_data(self):
        print('something....')

The error is :

Uncaught ReferenceError: get_patient_data is not defined

http://localhost:8069/appointment_webform:322
Traceback:
ReferenceError: get_patient_data is not defined
    at HTMLSelectElement.onchange (http://localhost:8069/appointment_webform:322:191)