class EmployeeAdmission(User):

    User.username = models.CharField(max_length=50)
    User.password = models.CharField(max_length=50)

    employee_number =models.CharField(max_length=10)
    joining_date = models.DateField()
    employee_first_name = models.CharField(max_length=20)
    employee_middle_name = models.CharField(max_length=20,blank=True)
    employee_last_name = models.CharField(max_length=20,blank=True)
    employee_email = models.EmailField(max_length=254)
    gender = models.CharField(choices=GENDER,max_length=20)
    date_of_birth = models.DateField()
    employee_category = models.ForeignKey(AddEmployeeCategory,on_delete=models.CASCADE,related_name='employee')
    job_title = models.CharField(max_length=35)
    qualification = models.CharField(max_length=30)
    Experience_info = models.TextField(max_length=200)
    total_experience = models.CharField(max_length=20,choices=YEAR)

@csrf_exempt
def post(self, request, format=None):
    json = JSONRenderer().render(request.data)
    stream = BytesIO(json)
    data = JSONParser().parse(stream)
    serializer = EmployeeDetailSerializer(data=data)
    if serializer.is_valid():

        category = serializer.fields.get('employee_category',default=None)

        if (category == 1 ):
            library_group = Group.objects.get(name='Library Management')
            request.user.groups.add(library_group)
            request.user.save()

        else :
            teacher_group = Group.objects.get(name='Teacher Management')
            request.user.groups.add(teacher_group)
            request.user.save()

        serializer.save()
        return Response(serializer.data, status=status.HTTP_201_CREATED)
    return Response(serializer.errors, status=status.HTTP_400_BAD_REQUEST)

request.user.groups.add(library_group)
request.user.save()

employee = serializer.save()

employee.groups.add(library_group)
employee.save()