diff --git a/Objects/unicodeobject.c b/Objects/unicodeobject.c
index f6473c0..4093555 100644
--- a/Objects/unicodeobject.c
+++ b/Objects/unicodeobject.c
@@ -42,6 +42,7 @@ OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 #include "Python.h"
 #include "pycore_abstract.h"      // _PyIndex_Check()
 #include "pycore_bytes_methods.h" // _Py_bytes_lower()
+#include "pycore_format.h"        // F_LJUST
 #include "pycore_initconfig.h"    // _PyStatus_OK()
 #include "pycore_interp.h"        // PyInterpreterState.fs_codec
 #include "pycore_object.h"        // _PyObject_GC_TRACK()