diff --git a/.azure-pipelines/syntax-validation.py b/.azure-pipelines/syntax-validation.py
index 6483683..9359ad8 100644
--- a/.azure-pipelines/syntax-validation.py
+++ b/.azure-pipelines/syntax-validation.py
@@ -12,7 +12,7 @@
             continue
         filename = os.path.normpath(os.path.join(base, f))
         try:
-            with open(filename, "r") as fh:
+            with open(filename) as fh:
                 ast.parse(fh.read())
         except SyntaxError as se:
             failures += 1
diff --git a/procrunner/__init__.py b/procrunner/__init__.py
index 8cc6bbb..31659ef 100644
--- a/procrunner/__init__.py
+++ b/procrunner/__init__.py
@@ -333,7 +333,7 @@
         if key in self._extras:
             return self._extras[key]
         if not hasattr(self, key):
-            raise KeyError("Unknown attribute {key}".format(key=key))
+            raise KeyError(f"Unknown attribute {key}")
         return getattr(self, key)
 
     def __eq__(self, other):