Added repeated fields.
diff --git a/python/repeated.h b/python/repeated.h
new file mode 100644
index 0000000..26d297c
--- /dev/null
+++ b/python/repeated.h
@@ -0,0 +1,61 @@
+/*
+ * Copyright (c) 2009-2021, Google LLC
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ * * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * * Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * * Neither the name of Google LLC nor the
+ * names of its contributors may be used to endorse or promote products
+ * derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL Google LLC BE LIABLE FOR ANY DIRECT,
+ * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef PYUPB_REPEATED_H__
+#define PYUPB_REPEATED_H__
+
+#include <stdbool.h>
+
+#include "python/python.h"
+#include "upb/def.h"
+
+// Creates a new repeated field in the unset state for field `f` of message
+// object `parent`.
+PyObject* PyUpb_RepeatedContainer_NewUnset(PyObject* parent,
+ const upb_fielddef* f,
+ PyObject* arena);
+
+// Returns a repeated field object wrapping `u_arr`, of field type `f`, which
+// must be on `arena`. If an existing wrapper object exists, it will be
+// returned, otherwise a new object will be created. The caller always owns a
+// ref on the returned value.
+PyObject* PyUpb_RepeatedContainer_GetOrCreateWrapper(upb_array* u_arr,
+ const upb_fielddef* f,
+ PyObject* arena);
+
+// Switches a repeated field in the unset state to be set, with `arr` as the
+// data being pointed to.
+void PyUpb_RepeatedContainer_SwitchToSet(PyObject* self, upb_array* arr);
+
+PyObject* PyUpb_RepeatedContainer_Extend(PyObject* _self, PyObject* value);
+PyObject* PyUpb_RepeatedCompositeContainer_Add(PyObject* _self, PyObject* args,
+ PyObject* kwargs);
+
+// Module-level init.
+bool PyUpb_Repeated_Init(PyObject* m);
+
+#endif // PYUPB_REPEATED_H__
