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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _get_editable(self, request):
 """ Get the dictionary of editable settings for a given request. Settings are fetched from the database once per request and then stored in ``_editable_caches``, a WeakKeyDictionary that will automatically discard each entry when no more references to the request exist. """

        try:
            editable_settings = self._editable_caches[request]
        except KeyError:
            editable_settings = self._editable_caches[request] = self._load()
        return editable_settings