def process_hash_keys(hash)
      return hash.inject({}) do |result, pair|
        key, value = pair
        result[key.to_sym] = value.is_a?(Hash) ?
            process_hash_keys(value) : value
        result
      end
    end
def process_hash_keys(hash)
      return hash.inject({}) do |result, pair|
        key, value = pair
        result[key.to_sym] = value.is_a?(Hash) ?
            process_hash_keys(value) : value
        result
      end
    end
Auxiliary method to recurse through a hash and convert all the keys to
 symbols.