diff --git a/stdlib/threading.codon b/stdlib/threading.codon
index c47b4de9..de077b09 100644
--- a/stdlib/threading.codon
+++ b/stdlib/threading.codon
@@ -1,3 +1,6 @@
+# (c) 2022 Exaloop Inc. All rights reserved.
+
+
 @tuple
 class Lock:
     p: cobj
@@ -5,20 +8,21 @@ class Lock:
     def __new__() -> Lock:
         return (_C.seq_lock_new(),)
 
-    def acquire(self, block: bool = True, timeout: float = -1.0):
+    def acquire(self, block: bool = True, timeout: float = -1.0) -> bool:
         if timeout >= 0.0 and not block:
             raise ValueError("can't specify a timeout for a non-blocking call")
         return _C.seq_lock_acquire(self.p, block, timeout)
 
-    def release(self):
+    def release(self) -> void:
         _C.seq_lock_release(self.p)
 
-    def __enter__(self):
+    def __enter__(self) -> void:
         self.acquire()
 
-    def __exit__(self):
+    def __exit__(self) -> void:
         self.release()
 
+
 @tuple
 class RLock:
     p: cobj
@@ -26,27 +30,32 @@ class RLock:
     def __new__() -> RLock:
         return (_C.seq_rlock_new(),)
 
-    def acquire(self, block: bool = True, timeout: float = -1.0):
+    def acquire(self, block: bool = True, timeout: float = -1.0) -> bool:
         if timeout >= 0.0 and not block:
             raise ValueError("can't specify a timeout for a non-blocking call")
         return _C.seq_rlock_acquire(self.p, block, timeout)
 
-    def release(self):
+    def release(self) -> void:
         _C.seq_rlock_release(self.p)
 
-    def __enter__(self):
+    def __enter__(self) -> void:
         self.acquire()
 
-    def __exit__(self):
+    def __exit__(self) -> void:
         self.release()
 
-def active_count():
+
+def active_count() -> int:
     from openmp import get_num_threads
+
     return get_num_threads()
 
-def get_native_id():
+
+def get_native_id() -> int:
     from openmp import get_thread_num
+
     return get_thread_num()
 
-def get_ident():
+
+def get_ident() -> int:
     return get_native_id() + 1