url(r'^login/$', views.UserLoginAPIView.as_view(), name='login'),
url(r'^api/auth/token/', obtain_jwt_token),

class UserLoginSerializer(ModelSerializer):
token = CharField(allow_blank=True, read_only= True)
email = EmailField(label='Email Address', allow_blank= True)

class Meta:
    model = User
    fields = [
        'email',
        'password',
        'token'
    ]

    extra_kwargs = {"password":
                        {"write_only": True}
                        }

def validate(self, data):
    user_obj = None
    email = data.get("email", None)
    password = data["password"]
    if not email:
        raise ValidationError('A username or email is required to login')
    user = User.objects.filter(
            Q(email=email)
        ).distinct()
    if user.exists() and user.count() == 1:
        user_obj = user.first()
    else:
        raise ValidationError("this email is not valid")

    if user_obj:
        if not user_obj.check_password(password):
            raise ValidationError("incorrect creadeintial try again")
    data["token"] = "SOME BLANK TOKEN"
    return data

class UserLoginAPIView(APIView):
permission_classes = [AllowAny]
serializer_class = UserLoginSerializer

def post(self, request, *args, **kwargs):
    data = request.data
    serializer = UserLoginSerializer(data=data)
    if serializer.is_valid(raise_exception=True):
        new_data = serializer.data
        return Response(new_data, status=HTTP_200_OK)
    return Response(serializer.errors, status=HTTP_400_BAD_REQUEST)