code: def elu(self, x, alpha=1):
      return np.where(x > 0, x, alpha * (np.expm1(x)))
  
imports: import pytest
  import numpy
  import theano.tensor
label_desc: Use image node_id 5 for calling the TestNonlinearities obj's underlying member method code with example usage: obj.elu(x, alpha) and returns: np