anchor.diff:  
   === Quick solution - Not scalable
   Let's say that you want to monitor a bunch of samples in BioSamples and
  -anytime a sample is updated you want to retrieve the new content into your system.
  +whenever a sample is updated you want to retrieve the new content into your system.
   
   One way of doing this is to have a list of accession and at a scheduled interval
   retrieve the samples from BioSamples and check if the update date on the sample
  
positive.code: ```
  curl -H "Accept: application/json" -H 'If-None-Match: <sample-etag-with-quotes>' -i https://www.ebi.ac.uk/biosamples/samples/<sample-accession>
  ```
  
negative.code: content-length: 1488
  ```
  
  === 2. Submit a new GET request including the ETAG
  
  Let's submit a new request with the `If-None-Match` header and the ETAG
  
  