Add jacobian and hessian

python/paddle/autograd/__init__.py

@@ -18,12 +18,15 @@
 from ..fluid.dygraph.base import is_grad_enabled  # noqa: F401
 from ..fluid.dygraph.base import set_grad_enabled  # noqa: F401
 from . import backward_mode  # noqa: F401
+from .autograd import jacobian, hessian  # noqa: F401
 from .backward_mode import backward  # noqa: F401
 from .py_layer import PyLayer  # noqa: F401
 from .py_layer import PyLayerContext  # noqa: F401
 from .saved_tensors_hooks import saved_tensors_hooks
 
 __all__ = [  # noqa
+    'jacobian',
+    'hessian',
     'backward',
     'PyLayer',
     'PyLayerContext',