[algorithms][models] Use new Environment object use_count method

beat/web/libraries/models.py

@@ -229,36 +229,17 @@ class Library(Code):
 
         Returns:
 
-          list: mapping environment to usage counts, determining how many times
-            a given algorithm has been successfully used on that environment
+          list: annotated environment with usage counts, determining how many times
+            a given library used in algorithms has been successfully used on that environment
 
         """
 
-        from django.db.models import Count, Q
         from ..experiments.models import Block
-        from ..experiments.models import Experiment
         from ..backend.models import Environment
 
         # Tries to figure through a maximum if using algorithms have been
         # successfully used inside an environment.
 
-        # Case 1) The block is part of an experiment that was successful
-        # Case 2) The block is part of an experiment that is not successful
-        # (failed or other), but it is CACHED (if not cached, then we can't
-        # attest anything about the algorithm/environment relationship!)
-
-        envs = (
-            Environment.objects.filter(
-                blocks__in=Block.objects.filter(
-                    algorithm__in=self.used_by_algorithms.all()
-                ).filter(
-                    Q(experiment__status=Experiment.DONE)
-                    | ((~Q(experiment__status=Experiment.DONE)) & Q(status=Block.DONE))
-                )
-            )
-            .annotate(itemcount=Count("id"))
-            .order_by("-creation_date")
-            .distinct()
+        return Environment.objects.use_count(
+            Block.objects.filter(algorithm__in=self.used_by_algorithms.all())
         )
-
-        return [(k, k.itemcount) for k in envs]