code: def testEmpty(self):
      self.assertAllClose(regularizers.L1(0.01)([]), 0.0)
  
file_path: sonnet/sonnet/src/regularizers_test.py
imports: import numpy
  from sonnet.src import regularizers
  from sonnet.src import test_utils
  import tensorflow
label_desc: Use image node_id 3 for calling the L1Test obj's underlying member method code with example usage: obj.testEmpty() without return types