code: def testSequenceWhichContainsEmptySequences(self):
      # yaml
      testFile = "foo: [[], []]"
      writeFile(testFile, "testfile")
  
      p = YamlInput(filename="testfile")()
      os.remove("testfile")
  
      self.assertEqualMatrix(p["foo"], [[], []])
  
      # to make sure that they are vectors of vectors Reals, try adding Reals
      # and strings
      self.assertRaises(KeyError, lambda: p.add("foo", ["foo", "bar"]))
  
      p.add("foo", [4])
      self.assertEqualMatrix(p["foo"], [[], [], [4]])
  
      # json
      testFile = '{ "foo": [[], []] }'
      writeFile(testFile, "testfile")
  
      p = YamlInput(filename="testfile", format="json")()
      os.remove("testfile")
  
      self.assertEqualMatrix(p["foo"], [[], []])
  
      # to make sure that they are vectors of vectors Reals, try adding Reals
      # and strings
      self.assertRaises(KeyError, lambda: p.add("foo", ["foo", "bar"]))
  
      p.add("foo", [4])
      self.assertEqualMatrix(p["foo"], [[], [], [4]])
  
imports: from essentia_test import *
  import os
label_desc: Use image node_id 12 for calling the TestYamlInput obj's underlying member method code with example usage: obj.testSequenceWhichContainsEmptySequences() without return types