Hi @rahul1 and team, I am using hello world app extending to test the practitioner registration. I am using medplum reactjs components. flow is simple - practitioner fill the form + upload his / her certificates and diploma... and bot is creating the resource. however looking at https://www.medplum.com/docs/api/fhir/resources/practitioner I can't find what field could be used to hold reference to the pdf uploaded. for example photo has Attachment type but what property should I use for different documents practitioner is uploading during registration ? should I use the extensions ? follow up question, uploading the file I see it is uploaded to s3 and I got a response with s3 path (url) it is stored. what is the best practices, should I use the url to assign the it to practitioner or there is a resource which incapsulated the url I looked for a multiple medplum repositories but I can't find example how to create practitioner with attachments ( documents ). please pointing me to the example how to implement (if any) or direction how to do it. Thanks.