fix cyclic imports errors

rest_models/backend/__init__.py

@@ -1,5 +0,0 @@
-# -*- coding: utf-8 -*-
-
-from rest_models.checks import register_checks
-
-register_checks()

rest_models/backend/compiler.py

@@ -23,6 +23,11 @@
 from rest_models.backend.utils import message_from_response
 from rest_models.router import RestModelRouter
 
+from rest_models.checks import register_checks
+
+register_checks()
+
+
 logger = logging.getLogger(__name__)
 
 Alias = namedtuple('Alias', 'model,parent,field,attrname,m2m')

rest_models/checks.py

@@ -6,13 +6,14 @@
 from django.apps import apps
 from django.core.checks import Error, Tags, register
 
-from rest_models.backend.compiler import get_resource_path
 from rest_models.router import RestModelRouter
 
 logger = logging.getLogger(__name__)
 
 
 def api_struct_check(app_configs, **kwargs):
+    from rest_models.backend.compiler import get_resource_path  # NOQA
+
     errors = []
 
     all_models = []