code: def __call__(self, x):
      return x * x
  
imports: import numpy
  import tensorflow.compat.v2
  from tensorflow.python.framework import test_util
  from tf_quant_finance.models.legacy import brownian_motion_utils
label_desc: Use image node_id 1 for calling the _TestClass2 obj's underlying member method code with example usage: obj.__call__(x) and returns: unknown