Fix documentation typo
diff --git a/buildstream/element.py b/buildstream/element.py
index fc21f80..3bdf972 100644
--- a/buildstream/element.py
+++ b/buildstream/element.py
@@ -65,7 +65,7 @@
 
 * :func:`Element.generate_script() <buildstream.element.Element.generate_script>`
 
-  For the purpose of ``bst source bundle``, an Element may optionally implmenent this.
+  For the purpose of ``bst source bundle``, an Element may optionally implement this.
 
 
 Class Reference