diff --git a/airflow/utils.py b/airflow/utils.py
index 6fc7071ebe279..cd36ad388a539 100644
--- a/airflow/utils.py
+++ b/airflow/utils.py
@@ -632,7 +632,7 @@ def default(self, obj):
         elif type(obj) in [numpy.bool_]:
             return bool(obj)
         elif type(obj) in [numpy.float_, numpy.float16, numpy.float32, numpy.float64,
-         numpy.complex_, numpy.complex64, numpy.complex128,:
+         numpy.complex_, numpy.complex64, numpy.complex128]:
             return float(obj)
 
         # Let the base class default method raise the TypeError