diff --git a/gstlal-inspiral/python/inspiral_pipe.py b/gstlal-inspiral/python/inspiral_pipe.py
index a54a109bbfebbb1905e3fd3396a9827ad56ff503..b1cf1ce90e7dfdc6410be7bcab17fa3723d4ae44 100644
--- a/gstlal-inspiral/python/inspiral_pipe.py
+++ b/gstlal-inspiral/python/inspiral_pipe.py
@@ -356,7 +356,7 @@ def T050017_filename(instruments, description, start, end, extension, path = Non
 	"""!
 	A function to generate a T050017 filename.
 	"""
-	if type(instruments) != type(str()):
+	if not isinstance(instruments, basestring):
 		instruments = "".join(sorted(instruments))
 	duration = end - start
 	extension = extension.strip('.')