code: def test_negative_timedelta(self):
      td_negative = datetime.timedelta(minutes=-1)
      with self.assertRaises(ValueError):
          format_timedelta(td_negative)
  
imports: import datetime
  import unittest
  from small_text.utils.datetime import format_timedelta
label_desc: Use image node_id 1 for calling the DatetimeUtilsTest obj's underlying member method code with example usage: obj.test_negative_timedelta() without return types