def deep_merge!(target, hash)
      hash.each do |key, value|
        target[key] = if value.is_a?(Hash) && target[key].is_a?(Hash)
                        deep_merge(target[key], value)
                      else
                        value
                      end
      end
      target
    end
def deep_merge!(target, hash)
      hash.each do |key, value|
        target[key] = if value.is_a?(Hash) && target[key].is_a?(Hash)
                        deep_merge(target[key], value)
                      else
                        value
                      end
      end
      target
    end
Recursive hash update