the first few links are just mostly references, you need to look a bit deeper. Like: <a href="https:&#x2F;&#x2F;python4astronomers.github.io&#x2F;astropy&#x2F;fits.html" rel="nofollow">https:&#x2F;&#x2F;python4astronomers.github.io&#x2F;astropy&#x2F;fits.html</a>