Cleanup in packaging: don’t unnecessarily instantiate exceptions
diff --git a/Lib/packaging/pypi/dist.py b/Lib/packaging/pypi/dist.py
index 16510df..db04cda 100644
--- a/Lib/packaging/pypi/dist.py
+++ b/Lib/packaging/pypi/dist.py
@@ -135,7 +135,7 @@
         not return one existing distribution.
         """
         if len(self.dists) == 0:
-            raise LookupError()
+            raise LookupError
         if dist_type:
             return self[dist_type]
         if prefer_source:
diff --git a/Lib/packaging/pypi/simple.py b/Lib/packaging/pypi/simple.py
index c492179..c372c6f 100644
--- a/Lib/packaging/pypi/simple.py
+++ b/Lib/packaging/pypi/simple.py
@@ -189,7 +189,7 @@
         self._process_index_page(predicate.name)
 
         if predicate.name.lower() not in self._projects:
-            raise ProjectNotFound()
+            raise ProjectNotFound
 
         releases = self._projects.get(predicate.name.lower())
         releases.sort_releases(prefer_final=prefer_final)