code: def create(self, parent=None, **relationships):
          
          if self.id:
              raise self.ResourceError('cannot create a resource with an existing ID')
          data = self.__class__._process_request(
              connection.post,
              parent=parent,
              payload=self.payload(),
              relationships=self._relationships_payload(relationships)
          )
          return self._reload(data)
docs: Creates the resource. This will trigger an api POST request.
          :param parent ResourceBase: the parent of the resource - used for nesting the request url, optional
          :param **relationships: any number of lists as keyword arguments to be submitted as relationships
              for the request, e.g. relationship_name=[resource1, resource2]
          :raises ResourceError: if the resource has an id (already exists)
          :returns: the resource itself