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diff --git a/circuitpython/py/objgetitemiter.c b/circuitpython/py/objgetitemiter.c
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+/*
+ * This file is part of the MicroPython project, http://micropython.org/
+ *
+ * The MIT License (MIT)
+ *
+ * SPDX-FileCopyrightText: Copyright (c) 2013, 2014 Damien P. George
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include <stdlib.h>
+
+#include "py/runtime.h"
+
+// this is a wrapper object that turns something that has a __getitem__ method into an iterator
+
+typedef struct _mp_obj_getitem_iter_t {
+    mp_obj_base_t base;
+    mp_obj_t args[3];
+} mp_obj_getitem_iter_t;
+
+STATIC mp_obj_t it_iternext(mp_obj_t self_in) {
+    mp_obj_getitem_iter_t *self = MP_OBJ_TO_PTR(self_in);
+    nlr_buf_t nlr;
+    if (nlr_push(&nlr) == 0) {
+        // try to get next item
+        mp_obj_t value = mp_call_method_n_kw(1, 0, self->args);
+        self->args[2] = MP_OBJ_NEW_SMALL_INT(MP_OBJ_SMALL_INT_VALUE(self->args[2]) + 1);
+        nlr_pop();
+        return value;
+    } else {
+        // an exception was raised
+        mp_obj_type_t *t = (mp_obj_type_t *)((mp_obj_base_t *)nlr.ret_val)->type;
+        if (t == &mp_type_StopIteration || t == &mp_type_IndexError) {
+            return MP_OBJ_STOP_ITERATION;
+        } else {
+            // re-raise exception
+            nlr_jump(nlr.ret_val);
+        }
+    }
+}
+
+STATIC const mp_obj_type_t mp_type_it = {
+    { &mp_type_type },
+    .flags = MP_TYPE_FLAG_EXTENDED,
+    .name = MP_QSTR_iterator,
+    MP_TYPE_EXTENDED_FIELDS(
+        .getiter = mp_identity_getiter,
+        .iternext = it_iternext,
+        ),
+};
+
+// args are those returned from mp_load_method_maybe (ie either an attribute or a method)
+mp_obj_t mp_obj_new_getitem_iter(mp_obj_t *args, mp_obj_iter_buf_t *iter_buf) {
+    assert(sizeof(mp_obj_getitem_iter_t) <= sizeof(mp_obj_iter_buf_t));
+    mp_obj_getitem_iter_t *o = (mp_obj_getitem_iter_t *)iter_buf;
+    o->base.type = &mp_type_it;
+    o->args[0] = args[0];
+    o->args[1] = args[1];
+    o->args[2] = MP_OBJ_NEW_SMALL_INT(0);
+    return MP_OBJ_FROM_PTR(o);
+}