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diff --git a/app/utils/deep_merge.py b/app/utils/deep_merge.py
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+###############################################################################
+# Copyright (c) 2017 Koren Lev (Cisco Systems), Yaron Yogev (Cisco Systems)   #
+# and others                                                                  #
+#                                                                             #
+# All rights reserved. This program and the accompanying materials            #
+# are made available under the terms of the Apache License, Version 2.0       #
+# which accompanies this distribution, and is available at                    #
+# http://www.apache.org/licenses/LICENSE-2.0                                  #
+###############################################################################
+"""
+Do a deep merge of dictionariesi,
+recursively merging dictionaries with boltons.iterutils.remap
+
+Taken from:
+https://gist.github.com/mahmoud/db02d16ac89fa401b968
+
+
+This is an extension of the technique first detailed here:
+http://sedimental.org/remap.html#add_common_keys
+In short, it calls remap on each container, back to front,
+using the accumulating previous values as the default for
+the current iteration.
+"""
+
+from boltons.iterutils import remap, get_path, default_enter, default_visit
+
+
+def remerge(target_list, sourced=False):
+    """
+    Takes a list of containers (e.g., dicts) and merges them using
+    boltons.iterutils.remap. Containers later in the list take
+    precedence (last-wins).
+    By default, returns a new, merged top-level container. With the
+    *sourced* option, `remerge` expects a list of (*name*, container*)
+    pairs, and will return a source map: a dictionary mapping between
+    path and the name of the container it came from.
+    """
+
+    if not sourced:
+        target_list = [(id(t), t) for t in target_list]
+
+    ret = None
+    source_map = {}
+
+    def remerge_enter(path, key, value):
+        new_parent, new_items = default_enter(path, key, value)
+        if ret and not path and key is None:
+            new_parent = ret
+            try:
+                cur_val = get_path(ret, path + (key,))
+            except KeyError:
+                pass
+            else:
+                # TODO: type check?
+                new_parent = cur_val
+
+        if isinstance(value, list):
+            # lists are purely additive.
+            # See https://github.com/mahmoud/boltons/issues/81
+            new_parent.extend(value)
+            new_items = []
+
+        return new_parent, new_items
+
+    for t_name, target in target_list:
+        if sourced:
+            def remerge_visit(path, key, value):
+                source_map[path + (key,)] = t_name
+                return True
+        else:
+            remerge_visit = default_visit
+
+        ret = remap(target, enter=remerge_enter, visit=remerge_visit)
+
+    if not sourced:
+        return ret
+    return ret, source_map