handle not found specificly depending on path

backend/tracim_backend/__init__.py

 # -*- coding: utf-8 -*-
-import os
-
-from tracim_backend.views.frontend import FrontendController
-
 try:  # Python 3.5+
     from http import HTTPStatus
 except ImportError:
 from pyramid.config import Configurator
 from pyramid.authentication import BasicAuthAuthenticationPolicy
 from hapic.ext.pyramid import PyramidContext
-from pyramid.exceptions import NotFound
 from sqlalchemy.exc import OperationalError
 
 from tracim_backend.extensions import hapic
 from tracim_backend.views.core_api.workspace_controller import WorkspaceController
 from tracim_backend.views.contents_api.comment_controller import CommentController
 from tracim_backend.views.contents_api.file_controller import FileController
+from tracim_backend.views.frontend import FrontendController
 from tracim_backend.views.errors import ErrorSchema
 from tracim_backend.exceptions import NotAuthenticated
+from tracim_backend.exceptions import PageNotFound
 from tracim_backend.exceptions import UserNotActive
 from tracim_backend.exceptions import InvalidId
 from tracim_backend.exceptions import InsufficientUserProfile
     hapic.set_context(context)
     # INFO - G.M - 2018-07-04 - global-context exceptions
     # Not found
-    context.handle_exception(NotFound, HTTPStatus.NOT_FOUND)
+    context.handle_exception(PageNotFound, HTTPStatus.NOT_FOUND)
     # Bad request
     context.handle_exception(WorkspaceNotFoundInTracimRequest, HTTPStatus.BAD_REQUEST)  # nopep8
     context.handle_exception(UserNotFoundInTracimRequest, HTTPStatus.BAD_REQUEST)  # nopep8

backend/tracim_backend/exceptions.py

 
 class TooShortAutocompleteString(TracimException):
     pass
+
+
+class PageNotFound(TracimException):
+    pass