code: def test_join_rows_are_tuples(self):
      new_table = self.left.join(
          self.right, "one", "four", columns=["four", "six"]
      )
  
      self.assertIsInstance(new_table.rows[0].values(), tuple)
  
imports: from agate import Table
  from agate.data_types import Number, Text
  from agate.testcase import AgateTestCase
label_desc: Use image node_id 18 for calling the TestJoin obj's underlying member method code with example usage: obj.test_join_rows_are_tuples() without return types