code: def generate_inputs(self):
      shape = self.shape
      dtype = self.dtype
      x = numpy.random.normal(-1, 1, shape).astype(dtype)
      return (x,)
  
imports: import chainer
  import chainerx
  import numpy
  from chainerx_tests import math_utils
  from chainerx_tests import op_utils
label_desc: Use image node_id 2 for calling the TestErf obj's underlying member method code with example usage: obj.generate_inputs() and returns: x