code: def testEmptyDict(self):
      with self.assertRaises(Exception):
          bar.Bars({})
  
file_path: pyalgotrade/testcases/bar_test.py
imports: import datetime
  from six.moves import cPickle
  from .None import common
  from pyalgotrade import bar
label_desc: Use image node_id 1 for calling the BarsTestCase obj's underlying member method code with example usage: obj.testEmptyDict() without return types