diff --git a/modes_reader.c b/modes_reader.c
index 7dfd96a..caf8693 100644
--- a/modes_reader.c
+++ b/modes_reader.c
@@ -532,15 +532,15 @@ static PyObject *radarcape_position_to_dict(uint8_t *data)
 {
     float lat, lon, alt;
 
-    lat = _PyFloat_Unpack4(data + 4, 1);
+    lat = PyFloat_Unpack4(data + 4, 1);
     if (lat == -1.0 && PyErr_Occurred())
         return NULL;
 
-    lon = _PyFloat_Unpack4(data + 8, 1);
+    lon = PyFloat_Unpack4(data + 8, 1);
     if (lon == -1.0 && PyErr_Occurred())
         return NULL;
 
-    alt = _PyFloat_Unpack4(data + 12, 1);
+    alt = PyFloat_Unpack4(data + 12, 1);
     if (alt == -1.0 && PyErr_Occurred())
         return NULL;