diff --git a/pyro/Enums/Event.py b/pyro/Enums/Event.py
index cd09612e..42f558bb 100644
--- a/pyro/Enums/Event.py
+++ b/pyro/Enums/Event.py
@@ -1,11 +1,15 @@
-class Event:
+from enum import Enum
+from typing import Union
+
+
+class BuildEvent(Enum):
     PRE = 0
     POST = 1
 
 
-class BuildEvent(Event):
-    pass
+class ImportEvent(Enum):
+    PRE = 0
+    POST = 1
 
 
-class ImportEvent(Event):
-    pass
+Event = Union[BuildEvent, ImportEvent]
diff --git a/pyro/ProcessManager.py b/pyro/ProcessManager.py
index e7a1dce5..ce42b634 100644
--- a/pyro/ProcessManager.py
+++ b/pyro/ProcessManager.py
@@ -28,7 +28,7 @@ def _format_time(hours: Decimal, minutes: Decimal, seconds: Decimal) -> str:
 
     @staticmethod
     def run_event(event_node: etree.ElementBase, project_path: str) -> None:
-        if not event_node:
+        if event_node is None:
             return
 
         ProcessManager.log.info(event_node.get(XmlAttributeName.DESCRIPTION))