text: from django.db import models
  from django.db.models.fields import AutoField, BooleanField, CharField, DateField, IntegerField, TimeField, TextField
  from django.db.models.fields.related import ForeignKey
  from visiting_schedule.models import VisitingSchedule
  from patient.models import Patient
  
  class Appointment(models.Model):
      APPOINTMENT_TYPE = (
          ('old','old'),
          ('report','report'),
          ('new','new')
      )
      appointmentId = AutoField(primary_key=True)
      appointmentPaymentCredential = CharField(max_length=11, blank= True)
      appointmentPatientSymptomNote = TextField(blank= True)
      appointmentTime = TimeField()
      appointmentIsConfirmed = BooleanField(default=False,blank= True)
      appointmentIsCanceled = BooleanField(default=False,blank= True)
      appointmentIsVisited = BooleanField(default=False,blank= True)
      appointmentDate = DateField()
      appointmentSerialNumber = IntegerField()
      appointmentType = CharField(max_length=11, choices=APPOINTMENT_TYPE)
      appointmentVisitingScheduleId = ForeignKey(VisitingSchedule, on_delete= models.CASCADE)
      appointmentPatientId = ForeignKey(Patient, on_delete= models.CASCADE)
  
      def __int__(self):
          return self.appointmentId