diff --git a/backend/api/models.py b/backend/api/models.py
index 58699dd4..61c12cd6 100644
--- a/backend/api/models.py
+++ b/backend/api/models.py
@@ -1,3 +1,4 @@
+import abc
 import random
 import string
 import uuid
@@ -39,7 +40,9 @@ class Project(PolymorphicModel):
     collaborative_annotation = models.BooleanField(default=False)
     single_class_classification = models.BooleanField(default=False)
 
-    def is_task_of(self, task: Literal['text', 'image', 'speech']):
+    @property
+    @abc.abstractmethod
+    def is_text_project(self) -> bool:
         raise NotImplementedError()
 
     def __str__(self):
@@ -48,40 +51,46 @@ class Project(PolymorphicModel):
 
 class TextClassificationProject(Project):
 
-    def is_task_of(self, task: Literal['text', 'image', 'speech']):
-        return task == 'text'
+    @property
+    def is_text_project(self) -> bool:
+        return True
 
 
 class SequenceLabelingProject(Project):
     allow_overlapping = models.BooleanField(default=False)
     grapheme_mode = models.BooleanField(default=False)
 
-    def is_task_of(self, task: Literal['text', 'image', 'speech']):
-        return task == 'text'
+    @property
+    def is_text_project(self) -> bool:
+        return True
 
 
 class Seq2seqProject(Project):
 
-    def is_task_of(self, task: Literal['text', 'image', 'speech']):
-        return task == 'text'
+    @property
+    def is_text_project(self) -> bool:
+        return True
 
 
 class IntentDetectionAndSlotFillingProject(Project):
 
-    def is_task_of(self, task: Literal['text', 'image', 'speech']):
-        return task == 'text'
+    @property
+    def is_text_project(self) -> bool:
+        return True
 
 
 class Speech2textProject(Project):
 
-    def is_task_of(self, task: Literal['text', 'image', 'speech']):
-        return task == 'speech'
+    @property
+    def is_text_project(self) -> bool:
+        return False
 
 
 class ImageClassificationProject(Project):
 
-    def is_task_of(self, task: Literal['text', 'image', 'speech']):
-        return task == 'image'
+    @property
+    def is_text_project(self) -> bool:
+        return False
 
 
 def generate_random_hex_color():
diff --git a/backend/api/views/auto_labeling.py b/backend/api/views/auto_labeling.py
index 6f9bbc31..137c0e17 100644
--- a/backend/api/views/auto_labeling.py
+++ b/backend/api/views/auto_labeling.py
@@ -142,7 +142,7 @@ class AutoLabelingConfigParameterTest(APIView):
 
     def prepare_example(self):
         text = self.request.data['text']
-        if self.project.is_task_of('text'):
+        if self.project.is_text_project:
             return text
         else:
             tu = TemporaryUpload.objects.get(upload_id=text)
@@ -221,7 +221,7 @@ class AutoLabelingAnnotation(generics.CreateAPIView):
 
     def get_example(self, project):
         example = get_object_or_404(Example, pk=self.kwargs['example_id'])
-        if project.is_task_of('text'):
+        if project.is_text_project:
             return example.text
         else:
             return str(example.filename)