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diff --git a/source/blender/blenkernel/BKE_persistent_data_handle.hh b/source/blender/blenkernel/BKE_persistent_data_handle.hh
new file mode 100644
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+++ b/source/blender/blenkernel/BKE_persistent_data_handle.hh
@@ -0,0 +1,132 @@
+/*
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ */
+
+#ifndef __BKE_PERSISTENT_DATA_HANDLE_H__
+#define __BKE_PERSISTENT_DATA_HANDLE_H__
+
+/** \file
+ * \ingroup bke
+ *
+ * A PersistentDataHandle is a weak reference to some data in a Blender file. The handle itself is
+ * just a number. A PersistentDataHandleMap is used to convert between handles and the actual data.
+ */
+
+#include "BLI_map.hh"
+
+#include "DNA_ID.h"
+
+struct Object;
+
+namespace blender::bke {
+
+class PersistentDataHandleMap;
+
+class PersistentDataHandle {
+ private:
+  /* Negative values indicate that the handle is "empty". */
+  int32_t handle_;
+
+  friend PersistentDataHandleMap;
+
+ protected:
+  PersistentDataHandle(int handle) : handle_(handle)
+  {
+  }
+
+ public:
+  PersistentDataHandle() : handle_(-1)
+  {
+  }
+
+  friend bool operator==(const PersistentDataHandle &a, const PersistentDataHandle &b)
+  {
+    return a.handle_ == b.handle_;
+  }
+
+  friend bool operator!=(const PersistentDataHandle &a, const PersistentDataHandle &b)
+  {
+    return !(a == b);
+  }
+
+  friend std::ostream &operator<<(std::ostream &stream, const PersistentDataHandle &a)
+  {
+    stream << a.handle_;
+    return stream;
+  }
+
+  uint64_t hash() const
+  {
+    return (uint64_t)handle_;
+  }
+};
+
+class PersistentIDHandle : public PersistentDataHandle {
+  friend PersistentDataHandleMap;
+  using PersistentDataHandle::PersistentDataHandle;
+};
+
+class PersistentObjectHandle : public PersistentIDHandle {
+  friend PersistentDataHandleMap;
+  using PersistentIDHandle::PersistentIDHandle;
+};
+
+class PersistentDataHandleMap {
+ private:
+  Map<int32_t, ID *> id_by_handle_;
+  Map<ID *, int32_t> handle_by_id_;
+
+ public:
+  void add(int32_t handle, ID &id)
+  {
+    BLI_assert(handle >= 0);
+    handle_by_id_.add(&id, handle);
+    id_by_handle_.add(handle, &id);
+  }
+
+  PersistentIDHandle lookup(ID *id) const
+  {
+    const int handle = handle_by_id_.lookup_default(id, -1);
+    return PersistentIDHandle(handle);
+  }
+
+  PersistentObjectHandle lookup(Object *object) const
+  {
+    const int handle = handle_by_id_.lookup_default((ID *)object, -1);
+    return PersistentObjectHandle(handle);
+  }
+
+  ID *lookup(const PersistentIDHandle &handle) const
+  {
+    ID *id = id_by_handle_.lookup_default(handle.handle_, nullptr);
+    return id;
+  }
+
+  Object *lookup(const PersistentObjectHandle &handle) const
+  {
+    ID *id = this->lookup((const PersistentIDHandle &)handle);
+    if (id == nullptr) {
+      return nullptr;
+    }
+    if (GS(id->name) != ID_OB) {
+      return nullptr;
+    }
+    return (Object *)id;
+  }
+};
+
+}  // namespace blender::bke
+
+#endif /*  __BKE_PERSISTENT_DATA_HANDLE_H__ */