code: def execute(self, **kwargs):
      
      assert self.resp is None, "Transaction already committed"
      try:
        self.resp = self.db.tx(list(self.edn_iter), **kwargs)
      except Exception:
        self.resp = False
        raise
      else:
        self.resolve()
        self.adds = None
        self.tmpents = None
      return self.resp
docs: commit the current statements from add()