Reimplement configmix.safe_merge() do to a deepcopy of all source configurations when merging. configmix.safe_merge() does now a deepcopy of all source configurations when merging. Changes in configuration instances after will not be reflected in the merged configuration any more.

# -*- coding: utf-8 -*-

key1 = u"in the root namespace"
key2 = u"in the root namespace -- too"

tree1 = {
    'key3': 0x20,

    'tree2': {
        'key4': u"get this as `tree1.tree2.key4'",
        'key5': True
    }
}