code: def test_valid_linestring(self):
      ls = geojson.LineString([(10, 5), (4, 3)])
      self.assertEqual(ls.is_valid, True)
  
imports: import unittest
  import geojson
label_desc: Use image node_id 2 for calling the TestValidationLineString obj's underlying member method code with example usage: obj.test_valid_linestring() without return types