docs: def delete_document(self, doc_uri):
          """Delete a document from an item
  
          :param doc_uri: the URI that references the document
          :type doc_uri: String
  
          :rtype: String
          :returns: a message confirming that the document was deleted
  
          :raises: APIError if the request was not successful
          """
  
          result = self.api_request(doc_uri, method='DELETE')
          return self.__check_success(result)