code: def _Ndtr(x):
      """Normal distribution function."""
      half_sqrt_2 = constant_op.constant(
          0.5 * np.sqrt(2.0), dtype=x.dtype, name="half_sqrt_2"
      )
      w = x * half_sqrt_2
      z = math_ops.abs(w)
      y = array_ops.where(
          z < half_sqrt_2,
          1.0 + math_ops.erf(w),
          array_ops.where(
              w > 0.0, 2.0 - math_ops.erfc(z), math_ops.erfc(z)
          ),
      )
      return 0.5 * y
  
file_path: tensorflow/tensorflow/python/ops/random_grad.py
imports: import numpy
  from tensorflow.python.framework import constant_op
  from tensorflow.python.framework import dtypes
  from tensorflow.python.framework import ops
  from tensorflow.python.ops import array_ops
  from tensorflow.python.ops import clip_ops
  from tensorflow.python.ops import gen_array_ops
  from tensorflow.python.ops import gen_random_ops
  from tensorflow.python.ops import math_ops
label_desc: Use image node_id 6 for calling a global function with example usage: _Ndtr(x) and returns: unknown