How to convert std::chrono::duration to double (seconds)

Let's have using duration = std::chrono::steady_clock::duration. I would like to convert duration to double in seconds with maximal precition elegantly.

I have found the reverse way (convert seconds as double to std::chrono::duration? ), but it didn't help me finding it out.

Alternatively expressed, I want optimally some std function double F(duration), which returns seconds.

Thank you.