def METHOD_NAME(self):
    """Check that the topic and tutorial are already there and retrieve them."""
    # check topic
    if not self.topic.exists():
        raise Exception("The topic %s does not exists. It should be created" % self.topic.name)
    self.topic.init_from_metadata()
    # initiate the tutorial
    self.tuto = Tutorial(training=self, topic=self.topic)
    self.tuto.init_from_existing_tutorial(self.kwds["tutorial_name"])
    if "datatypes" in self.kwds:
        self.tuto.datatype_fp = self.kwds["datatypes"]
    if "workflow" in self.kwds:
        self.tuto.init_wf_fp = self.kwds["workflow"]
    if "workflow_id" in self.kwds:
        self.tuto.init_wf_id = self.kwds["workflow_id"]