diff --git a/src/engineio/__init__.py b/src/engineio/__init__.py
index b87baf0c..e63d5ad5 100644
--- a/src/engineio/__init__.py
+++ b/src/engineio/__init__.py
@@ -17,8 +17,6 @@
     get_tornado_handler = None
     ASGIApp = None
 
-__version__ = '4.2.1dev'
-
 __all__ = ['__version__', 'Server', 'WSGIApp', 'Middleware', 'Client']
 if AsyncServer is not None:  # pragma: no cover
     __all__ += ['AsyncServer', 'ASGIApp', 'get_tornado_handler',