[PATCH] Fix compilation for Python 3.9

--- pyo-1.0.3/src/objects/bandsplitmodule.c.orig	2020-10-28 16:16:04.880183146 +0100
+++ pyo-1.0.3/src/objects/bandsplitmodule.c	2020-10-28 16:37:45.918725734 +0100
@@ -1636,7 +1636,7 @@
 static PyObject *
 MultiBandMain_setFrequencies(MultiBandMain* self, PyObject *arg) {
     int i, bounds = self->nbands - 1;
-    if PyList_Check(arg) {
+    if (PyList_Check(arg)) {
         if (PyList_Size(arg) == bounds) {
             for (i=0; i<bounds; i++) {
                 MultiBandMain_compute_variables(self, PyFloat_AsDouble(PyList_GetItem(arg, i)), i);