code: def test_line_chart(self):
      text = self.tablesets.line_chart(x="two", y="three")
      svg = self.parse_svg(text)
  
      self.assertElementCount(svg, ".axis", 6)
      self.assertElementCount(svg, ".series", 3)
      self.assertElementCount(svg, "path", 3)
  
      text2 = self.tablesets.line_chart(x=1, y=2)
      self.assertEqual(text, text2)
  
file_path: agate/tests/test_tableset/test_charting.py
imports: from collections import OrderedDict
  import leather
  from agate import Table, TableSet
  from agate.data_types import Number, Text
label_desc: Use image node_id 4 for calling the TestTableSetCharts obj's underlying member method code with example usage: obj.test_line_chart() without return types