curl --request POST \
  --url {schemes}://api.upsun.com/users/{user_id}/emailaddress \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "email_address": "jsmith@example.com"
}
'

{
  "status": "<string>",
  "message": "<string>",
  "code": 123,
  "detail": {},
  "title": "<string>"
}