# File lib/mongo_mapper/plugins/keys.rb, line 39
        def dealias_keys(hash)
          out = {}
          hash.each do |k, v|
            key = keys[k.to_s]
            name = key && key.abbr || k
            out[name] = k.to_s.match(/^\$/) && v.is_a?(Hash) ? dealias_keys(v) : v
          end
          out
        end