code: def testBounded(self):
      ratio = self.__buildRatio([-1, -2, -1], 2)
      self.assertEqual(ratio[0], -1)
      self.assertEqual(ratio[1], 0.5)
      self.assertEqual(len(ratio), 2)
  
file_path: pyalgotrade/testcases/technical_ratio_test.py
imports: from .None import common
  from pyalgotrade.technical import ratio
  from pyalgotrade import dataseries
label_desc: Use image node_id 4 for calling the TestCase obj's underlying member method code with example usage: obj.testBounded() without return types