diff --git a/python/tests/valgrind-python.supp b/python/tests/valgrind-python.supp
index b4e0177033..01bc776aec 100644
--- a/python/tests/valgrind-python.supp
+++ b/python/tests/valgrind-python.supp
@@ -213,6 +213,19 @@
    fun:__Pyx__PyObject_CallOneArg
 }
 
+{
+   other
+   Memcheck:Leak
+   match-leak-kinds: definite
+   fun:realloc
+   fun:resize_compact
+   fun:_PyUnicodeWriter_Finish
+   fun:PyUnicode_FromFormatV
+   fun:PyUnicode_FromFormat
+   fun:PyFortranObject_NewAsAttr
+   ...
+}
+
 {
    other
    Memcheck:Value8