"AttributeError: 'MyUser' object has no attribute 'update'"

models.py

class MyUserManager(BaseUserManager):
    def create(self, email, name, birthday, sex, password):
        return self.create_user(email=email,
                                password=password,
                                name=name,
                                birthday=birthday,
                                sex=sex,
        )

    def create_user(self, email, name, birthday, sex, password):
        if not email:
            raise ValueError(_('email cannot be blank.'))
 
        user = self.model(
            email=MyUserManager.normalize_email(email),
            name=name,
            birthday=birthday,
            sex=sex,
            is_active=True,
        )

        user.set_password(password)
        user.save(using=self._db)
        return user
 
    def create_superuser(self, email, name, birthday, sex, password):
        user = self.create_user(email=email,
            password=password,
            name=name,
            birthday=birthday,
            sex=sex,
        )
        user.is_staff=True
        user.is_superuser=True
        user.is_admin=True
        user.save(using=self._db)

        return user

class MyUser(AbstractBaseUser, PermissionsMixin):
    email = models.EmailField(max_length=254, unique=True, db_index=True)
    name = models.CharField(max_length=254)
    birthday = models.DateField()
    sex = models.SmallIntegerField()

    creation = models.DateTimeField(auto_now_add=True)
    modification = models.DateTimeField(auto_now=True)

    objects = MyUserManager()

    is_staff = models.BooleanField(default=False, blank=True,)
    is_active = models.BooleanField(default=True, blank=True,)

    def get_absolute_url(self):
        return reverse('vomuser-detail', args=[str(self.id)])

    def __unicode__(self):
        return self.email

    def has_perm(self, perm, obj=None):
        return super(VomUser, self).has_perm(perm, obj)

    def has_module_perms(self, app_label):
        return super(VomUser, self).has_module_perms(app_label)

    def get_short_name(self):
        return self.name

    def get_username(self):
        return self.name

    USERNAME_FIELD = 'email'
    REQUIRED_FIELDS = ['name', 'birthday', 'sex', ]

serializers.py

class ChangePasswordSerializer(serializers.Serializer):
    current_password = serializers.CharField()
    new_password = serializers.CharField()
    new_password2 = serializers.CharField()

    def validate_current_password(self, attrs, source):
        # http://goo.gl/5Frj9Z
        if not self.object.check_password(attrs["current_password"]):
            raise serializers.ValidationError(
                _("Current password is not correct"),
                code='password_wrong',
            )

        return attrs

    def validate_new_password2(self, attrs, source):
        if attrs["new_password"] != attrs["new_password2"]:
            raise serializers.ValidationError(
                _("This field must be matched by password field."),
                code='password_mismatch',
            )

        return attrs

    def restore_object(self, attrs, instance=None):
        """ change password """
        user = super(ChangePasswordSerializer, self).restore_object(attrs,
                                                                    instance)
        if instance is not None:
            instance.set_password(attrs['new_password2'])
            return instance
        
        return user

views.py

@api_view(['PATCH'])
@permission_classes((custom_permissions.permissions.IsAuthenticated, ))
def changePassword(request):
    import ipdb; ipdb.set_trace()
    serializer = serializers.ChangePasswordSerializer(request.user,
                                                    request.DATA,)

    if serializer.is_valid():
        serializer.save()
        return Response(status=status.HTTP_204_NO_CONTENT)

    return Response(serializer.errors, status=status.HTTP_400_BAD_REQUEST)