diff --git a/Objects/bufferobject.c b/Objects/bufferobject.c
index eb02e32..dd25668 100644
--- a/Objects/bufferobject.c
+++ b/Objects/bufferobject.c
@@ -319,13 +319,13 @@
 	const char *status = self->b_readonly ? "read-only" : "read-write";
 
 	if ( self->b_base == NULL )
-		return PyString_FromFormat("<%s buffer ptr %p, size %zd at %p>",
+		return PyUnicode_FromFormat("<%s buffer ptr %p, size %zd at %p>",
 					   status,
 					   self->b_ptr,
 					   self->b_size,
 					   self);
 	else
-		return PyString_FromFormat(
+		return PyUnicode_FromFormat(
 			"<%s buffer for %p, size %zd, offset %zd at %p>",
 			status,
 			self->b_base,