fix callbacks to copy it always

Author: kumaraditya303

Modules/_asynciomodule.c

@@ -1265,52 +1265,49 @@ static PyObject *
 FutureObj_get_callbacks(FutureObj *fut, void *Py_UNUSED(ignored))
 {
     asyncio_state *state = get_asyncio_state_by_def((PyObject *)fut);
-    Py_ssize_t i;
-
     ENSURE_FUTURE_ALIVE(state, fut)
 
-    if (fut->fut_callback0 == NULL) {
-        if (fut->fut_callbacks == NULL) {
-            Py_RETURN_NONE;
-        }
-
-        return Py_NewRef(fut->fut_callbacks);
+    if (fut->fut_callback0 == NULL && fut->fut_callbacks == NULL) {
+        Py_RETURN_NONE;
     }
 
-    Py_ssize_t len = 1;
+    Py_ssize_t len = 0;
+    if (fut->fut_callback0 != NULL) {
+        len++;
+    }
     if (fut->fut_callbacks != NULL) {
         len += PyList_GET_SIZE(fut->fut_callbacks);
     }
 
-
-    PyObject *new_list = PyList_New(len);
-    if (new_list == NULL) {
+    PyObject *callbacks = PyList_New(len);
+    if (callbacks == NULL) {
         return NULL;
     }
 
-    PyObject *tup0 = PyTuple_New(2);
-    if (tup0 == NULL) {
-        Py_DECREF(new_list);
-        return NULL;
+    Py_ssize_t i = 0;
+    if (fut->fut_callback0 != NULL) {
+        PyObject *tup0 = PyTuple_New(2);
+        if (tup0 == NULL) {
+            Py_DECREF(callbacks);
+            return NULL;
+        }
+        PyTuple_SET_ITEM(tup0, 0, Py_NewRef(fut->fut_callback0));
+        assert(fut->fut_context0 != NULL);
+        PyTuple_SET_ITEM(tup0, 1, Py_NewRef(fut->fut_context0));
+        PyList_SET_ITEM(callbacks, i, tup0);
+        i++;
     }
 
-    Py_INCREF(fut->fut_callback0);
-    PyTuple_SET_ITEM(tup0, 0, fut->fut_callback0);
-    assert(fut->fut_context0 != NULL);
-    Py_INCREF(fut->fut_context0);
-    PyTuple_SET_ITEM(tup0, 1, (PyObject *)fut->fut_context0);
-
-    PyList_SET_ITEM(new_list, 0, tup0);
-
     if (fut->fut_callbacks != NULL) {
-        for (i = 0; i < PyList_GET_SIZE(fut->fut_callbacks); i++) {
-            PyObject *cb = PyList_GET_ITEM(fut->fut_callbacks, i);
+        for (int j = 0; i < PyList_GET_SIZE(fut->fut_callbacks); j++) {
+            PyObject *cb = PyList_GET_ITEM(fut->fut_callbacks, j);
             Py_INCREF(cb);
-            PyList_SET_ITEM(new_list, i + 1, cb);
+            PyList_SET_ITEM(callbacks, i, cb);
+            i++;
         }
     }
 
-    return new_list;
+    return callbacks;
 }
 
 static PyObject *