add simplest possible PyDict_Values

Author: timfel

graalpython/com.oracle.graal.python.cext/src/dictobject.c

@@ -207,3 +207,8 @@ UPCALL_ID(PyDict_Merge);
 int PyDict_Merge(PyObject *a, PyObject *b, int override) {
     return UPCALL_CEXT_I(_jls_PyDict_Merge, native_to_java(a), native_to_java(b), override);
 }
+
+UPCALL_ID(PyDict_Values);
+PyObject * PyDict_Values(PyObject *dict) {
+    return UPCALL_CEXT_O(_jls_PyDict_Values, native_to_java(dict));
+}

graalpython/lib-graalpython/python_cext.py

@@ -218,6 +218,10 @@ def PyDict_Merge(a, b, override):
                 a[k] = b[k]
     return 0
 
+@may_raise
+def PyDict_Values(d):
+    return list(d.values())
+
 ##################### SET, FROZENSET