fix import complete_social_login

Author: asudoma

rest_auth/registration/serializers.py

@@ -5,13 +5,13 @@
 from requests.exceptions import HTTPError
 # Import is needed only if we are using social login, in which
 # case the allauth.socialaccount will be declared
-try:
-    from allauth.socialaccount.helpers import complete_social_login
-except ImportError:
-    raise ImportError('allauth.socialaccount needs to be installed.')
 
-if 'allauth.socialaccount' not in settings.INSTALLED_APPS:
-    raise ImportError('allauth.socialaccount needs to be added to INSTALLED_APPS.')
+if 'allauth.socialaccount' in settings.INSTALLED_APPS:
+    try:
+        from allauth.socialaccount.helpers import complete_social_login
+    except ImportError:
+        pass
+
 
 
 class SocialLoginSerializer(serializers.Serializer):