docs: def content_info(self, key, model, contentid, vendor=None):
          """(Speculation) Fetches content information for a given vendor, model, and ID.
  
          This method might map to:
          https://github.com/exosite/docs/tree/master/provision#get---get-content-info-1,
          but seems to be missing serial number.
  
          Args:
              key: The CIK or Token for the device
              model:
              contentid: The ID used to name the entity bucket
              vendor: The name of the vendor
          """
          if not vendor:  # if no vendor name, key should be the owner one
              path = PROVISION_MANAGE_CONTENT + model + '/' + contentid
              return self._request(path, key, '', 'GET', self._manage_by_cik)
          else:  # if provide vendor name, key can be the device one
              data = urlencode({'vendor': vendor,
                                'model': model,
                                'id': contentid,
                                'info': 'true'})
              return self._request(PROVISION_DOWNLOAD,
                                   key, data, 'GET', self._manage_by_cik)