PyCountry memory patch

gistfile1.diff

diff --git a/src/pycountry/db.py b/src/pycountry/db.py
index 38689ed..aeb8640 100644
--- a/src/pycountry/db.py
+++ b/src/pycountry/db.py
@@ -45,6 +45,7 @@ class Database(object):
                     entry.attributes.get(key).value)
             entry_obj = self.data_class(entry, **mapped_data)
             self.objects.append(entry_obj)
+        tree.unlink()
 
         # Construct list of indices: primary single-column indices
         indices = []