message: Update the documentation of batch_jacobian to make the default behavior more explicit.
diff: @@ -95,8 +95,11 @@ def batch_jacobian(output, inp, use_pfor=True, parallel_iterations=None):
  inp: A tensor with shape [b, x1, ..., x_m]
  use_pfor: If true, uses pfor for computing the Jacobian. Else uses a
  tf.while_loop.
  - parallel_iterations: A knob to control how many iterations and dispatched in
  - parallel. This knob can be used to control the total memory usage.
  + parallel_iterations: A knob to control how many iterations are vectorized
  + and dispatched in parallel. The default value of None, when use_pfor is
  + true, corresponds to vectorizing all the iterations. When use_pfor is
  + false, the default value of None corresponds to parallel_iterations=10.
  + This knob can be used to control the total memory usage.
  Returns:
  A tensor `t` with shape [b, y_1, ..., y_n, x1, ..., x_m] where `t[i, ...]`
  