X-Git-Url: https://git.mdrn.pl/redakcja.git/blobdiff_plain/13f286427e0ceb7a6c442844c447c7c3d5495871..94da7eb2739d91e80607681bc61672ef769ca90c:/src/catalogue/models.py

diff --git a/src/catalogue/models.py b/src/catalogue/models.py
index 151a13e4..6f4fa1e9 100644
--- a/src/catalogue/models.py
+++ b/src/catalogue/models.py
@@ -294,6 +294,12 @@ class Book(WikidataModel):
         if b.project is None: return ''
         return b.project.name
 
+    def audience(self):
+        try:
+            return self.document_books.first().wldocument().book_info.audience or ''
+        except:
+            return ''
+
     def get_estimated_costs(self):
         return {
             work_type: work_type.calculate(self)
@@ -314,6 +320,9 @@ class Book(WikidataModel):
         if pbr is not None and pbr.timestamp.date() > cutoff:
             months = (this_month - pbr.timestamp.date()).days / 365 * 12
 
+        if not months:
+            return
+
         stats = self.bookmonthlystats_set.filter(date__gte=cutoff).aggregate(
             views_page=models.Sum('views_page'),
             views_reader=models.Sum('views_reader')