diff --git a/lib/python/pyflyby/_parse.py b/lib/python/pyflyby/_parse.py
index 1740ca4a..5ed3654f 100644
--- a/lib/python/pyflyby/_parse.py
+++ b/lib/python/pyflyby/_parse.py
@@ -965,7 +965,6 @@ def from_text(cls, text, filename=None, startpos=None, flags=None,
         """
         if isinstance(filename, str):
             filename = Filename(filename)
-            assert False
         assert isinstance(filename, (Filename, types.NoneType)), filename
         text = FileText(text, filename=filename, startpos=startpos)
         self = object.__new__(cls)