code: def test_first_defaults_to_None(self):
      rows = records.RecordCollection(iter([]))
      assert rows.first() is None
  
imports: from collections import namedtuple
  import records
  from pytest import raises
label_desc: Use image node_id 8 for calling the TestRecordCollection obj's underlying member method code with example usage: obj.test_first_defaults_to_None() without return types