fix API python example (#17226)

* fix api example. test=develop

* fix API.spec. test=develop

* fix spectral_norm format. test=develpp

* merge develop

* add import. test=develop

* fix indent. test=develop

* fix indent. test=develop

* add import fluid. test=develop

paddle/fluid/API.spec

@@ -93,7 +93,7 @@ paddle.fluid.layers.softmax (ArgSpec(args=['input', 'use_cudnn', 'name', 'axis']
 paddle.fluid.layers.pool2d (ArgSpec(args=['input', 'pool_size', 'pool_type', 'pool_stride', 'pool_padding', 'global_pooling', 'use_cudnn', 'ceil_mode', 'name', 'exclusive'], varargs=None, keywords=None, defaults=(-1, 'max', 1, 0, False, True, False, None, True)), ('document', 'bbd84e855e660cd1084bb71a2fd0cdaa'))
 paddle.fluid.layers.pool3d (ArgSpec(args=['input', 'pool_size', 'pool_type', 'pool_stride', 'pool_padding', 'global_pooling', 'use_cudnn', 'ceil_mode', 'name', 'exclusive'], varargs=None, keywords=None, defaults=(-1, 'max', 1, 0, False, True, False, None, True)), ('document', '043de7333b79ee0ac55053c14ed81625'))
 paddle.fluid.layers.adaptive_pool2d (ArgSpec(args=['input', 'pool_size', 'pool_type', 'require_index', 'name'], varargs=None, keywords=None, defaults=('max', False, None)), ('document', '859b887174d06f361658f69cb7c06d95'))
-paddle.fluid.layers.adaptive_pool3d (ArgSpec(args=['input', 'pool_size', 'pool_type', 'require_index', 'name'], varargs=None, keywords=None, defaults=('max', False, None)), ('document', '120f4323a3d7ed9c0916f15a59f0e497'))
+paddle.fluid.layers.adaptive_pool3d (ArgSpec(args=['input', 'pool_size', 'pool_type', 'require_index', 'name'], varargs=None, keywords=None, defaults=('max', False, None)), ('document', '55db6ae7275fb9678a6814aebab81a9c'))
 paddle.fluid.layers.batch_norm (ArgSpec(args=['input', 'act', 'is_test', 'momentum', 'epsilon', 'param_attr', 'bias_attr', 'data_layout', 'in_place', 'name', 'moving_mean_name', 'moving_variance_name', 'do_model_average_for_mean_and_var', 'fuse_with_relu', 'use_global_stats'], varargs=None, keywords=None, defaults=(None, False, 0.9, 1e-05, None, None, 'NCHW', False, None, None, None, False, False, False)), ('document', '581f9f99cd7f4b0cab9e0aad5fa0ea24'))
 paddle.fluid.layers.data_norm (ArgSpec(args=['input', 'act', 'epsilon', 'param_attr', 'data_layout', 'in_place', 'name', 'moving_mean_name', 'moving_variance_name', 'do_model_average_for_mean_and_var'], varargs=None, keywords=None, defaults=(None, 1e-05, None, 'NCHW', False, None, None, None, False)), ('document', '2460b30fb87037555208fa8ac6fc1787'))
 paddle.fluid.layers.beam_search_decode (ArgSpec(args=['ids', 'scores', 'beam_size', 'end_id', 'name'], varargs=None, keywords=None, defaults=(None,)), ('document', 'b0b8d53821716cd50c42e09b593f3feb'))
@@ -133,7 +133,7 @@ paddle.fluid.layers.row_conv (ArgSpec(args=['input', 'future_context_size', 'par
 paddle.fluid.layers.multiplex (ArgSpec(args=['inputs', 'index'], varargs=None, keywords=None, defaults=None), ('document', '2c4d1ae83da6ed35e3b36ba1b3b51d23'))
 paddle.fluid.layers.layer_norm (ArgSpec(args=['input', 'scale', 'shift', 'begin_norm_axis', 'epsilon', 'param_attr', 'bias_attr', 'act', 'name'], varargs=None, keywords=None, defaults=(True, True, 1, 1e-05, None, None, None, None)), ('document', 'de6a906950bae9f3c245cb744d22b94e'))
 paddle.fluid.layers.group_norm (ArgSpec(args=['input', 'groups', 'epsilon', 'param_attr', 'bias_attr', 'act', 'data_layout', 'name'], varargs=None, keywords=None, defaults=(1e-05, None, None, None, 'NCHW', None)), ('document', '419c3a24a83cc89219a029cf4092788b'))
-paddle.fluid.layers.spectral_norm (ArgSpec(args=['weight', 'dim', 'power_iters', 'eps', 'name'], varargs=None, keywords=None, defaults=(0, 1, 1e-12, None)), ('document', '3f536aafba30d793287b52d231baff1b'))
+paddle.fluid.layers.spectral_norm (ArgSpec(args=['weight', 'dim', 'power_iters', 'eps', 'name'], varargs=None, keywords=None, defaults=(0, 1, 1e-12, None)), ('document', '9461e67095a6fc5d568fb2ce8fef66ff'))
 paddle.fluid.layers.softmax_with_cross_entropy (ArgSpec(args=['logits', 'label', 'soft_label', 'ignore_index', 'numeric_stable_mode', 'return_softmax', 'axis'], varargs=None, keywords=None, defaults=(False, -100, True, False, -1)), ('document', '8b074f9c56b4233a2b65d03254eb309e'))
 paddle.fluid.layers.smooth_l1 (ArgSpec(args=['x', 'y', 'inside_weight', 'outside_weight', 'sigma'], varargs=None, keywords=None, defaults=(None, None, None)), ('document', 'c6b175d253c55baf4b9c0eca9b1dda88'))
 paddle.fluid.layers.one_hot (ArgSpec(args=['input', 'depth'], varargs=None, keywords=None, defaults=None), ('document', '960fc799549c202da1e85d626cb2c962'))
@@ -216,7 +216,7 @@ paddle.fluid.layers.sequence_reverse (ArgSpec(args=['x', 'name'], varargs=None,
 paddle.fluid.layers.affine_channel (ArgSpec(args=['x', 'scale', 'bias', 'data_layout', 'name', 'act'], varargs=None, keywords=None, defaults=(None, None, 'NCHW', None, None)), ('document', 'ab84fdc6dc60f3ad9aa397e6007e3bf9'))
 paddle.fluid.layers.similarity_focus (ArgSpec(args=['input', 'axis', 'indexes', 'name'], varargs=None, keywords=None, defaults=(None,)), ('document', '6f90d6ff76bf4f5e592332c1ef28494e'))
 paddle.fluid.layers.hash (ArgSpec(args=['input', 'hash_size', 'num_hash', 'name'], varargs=None, keywords=None, defaults=(1, None)), ('document', '97bf4353bb046a5629308a38f98ac204'))
-paddle.fluid.layers.grid_sampler (ArgSpec(args=['x', 'grid', 'name'], varargs=None, keywords=None, defaults=(None,)), ('document', 'd256cba1c41a5ed92ce3f31e24a2ca6d'))
+paddle.fluid.layers.grid_sampler (ArgSpec(args=['x', 'grid', 'name'], varargs=None, keywords=None, defaults=(None,)), ('document', '5d16663e096d7f04954c70ce1cc5e195'))
 paddle.fluid.layers.log_loss (ArgSpec(args=['input', 'label', 'epsilon', 'name'], varargs=None, keywords=None, defaults=(0.0001, None)), ('document', 'af541e9263be61ce0e40df58d1b69294'))
 paddle.fluid.layers.add_position_encoding (ArgSpec(args=['input', 'alpha', 'beta', 'name'], varargs=None, keywords=None, defaults=(None,)), ('document', '4b9c2e8af5817937d831820874b5aa77'))
 paddle.fluid.layers.bilinear_tensor_product (ArgSpec(args=['x', 'y', 'size', 'act', 'name', 'param_attr', 'bias_attr'], varargs=None, keywords=None, defaults=(None, None, None, None)), ('document', 'cd0bd55ef1e1762aca25ec972d34d378'))
@@ -363,9 +363,9 @@ paddle.fluid.layers.box_decoder_and_assign (ArgSpec(args=['prior_box', 'prior_bo
 paddle.fluid.layers.collect_fpn_proposals (ArgSpec(args=['multi_rois', 'multi_scores', 'min_level', 'max_level', 'post_nms_top_n', 'name'], varargs=None, keywords=None, defaults=(None,)), ('document', '82ffd896ecc3c005ae1cad40854dcace'))
 paddle.fluid.layers.accuracy (ArgSpec(args=['input', 'label', 'k', 'correct', 'total'], varargs=None, keywords=None, defaults=(1, None, None)), ('document', 'ef799022a6040597462ae2b3d2f1c407'))
 paddle.fluid.layers.auc (ArgSpec(args=['input', 'label', 'curve', 'num_thresholds', 'topk', 'slide_steps'], varargs=None, keywords=None, defaults=('ROC', 4095, 1, 1)), ('document', '300537e259bba86fdefa13a133a0587d'))
-paddle.fluid.layers.exponential_decay (ArgSpec(args=['learning_rate', 'decay_steps', 'decay_rate', 'staircase'], varargs=None, keywords=None, defaults=(False,)), ('document', '98a5050bee8522fcea81aa795adaba51'))
-paddle.fluid.layers.natural_exp_decay (ArgSpec(args=['learning_rate', 'decay_steps', 'decay_rate', 'staircase'], varargs=None, keywords=None, defaults=(False,)), ('document', '676a7bc2a218691db50bca233903d21e'))
-paddle.fluid.layers.inverse_time_decay (ArgSpec(args=['learning_rate', 'decay_steps', 'decay_rate', 'staircase'], varargs=None, keywords=None, defaults=(False,)), ('document', 'd07e767d59c4a5e6c930f3e6756d3f82'))
+paddle.fluid.layers.exponential_decay (ArgSpec(args=['learning_rate', 'decay_steps', 'decay_rate', 'staircase'], varargs=None, keywords=None, defaults=(False,)), ('document', 'eaf430c5a0380fb11bfe9a8922cd6295'))
+paddle.fluid.layers.natural_exp_decay (ArgSpec(args=['learning_rate', 'decay_steps', 'decay_rate', 'staircase'], varargs=None, keywords=None, defaults=(False,)), ('document', '63a9e96d446d7de1289f30b832bce36a'))
+paddle.fluid.layers.inverse_time_decay (ArgSpec(args=['learning_rate', 'decay_steps', 'decay_rate', 'staircase'], varargs=None, keywords=None, defaults=(False,)), ('document', 'ea37a3a8a0b3ce2254e7bc49a0951dbe'))
 paddle.fluid.layers.polynomial_decay (ArgSpec(args=['learning_rate', 'decay_steps', 'end_learning_rate', 'power', 'cycle'], varargs=None, keywords=None, defaults=(0.0001, 1.0, False)), ('document', 'a343254c36c2e89512cd8cd8a1960ead'))
 paddle.fluid.layers.piecewise_decay (ArgSpec(args=['boundaries', 'values'], varargs=None, keywords=None, defaults=None), ('document', 'd9f654117542c6b702963dda107a247f'))
 paddle.fluid.layers.noam_decay (ArgSpec(args=['d_model', 'warmup_steps'], varargs=None, keywords=None, defaults=None), ('document', 'f96805b1a64f9a12f4627497e5fcb920'))

python/paddle/fluid/layers/learning_rate_scheduler.py

@@ -124,14 +124,14 @@ def exponential_decay(learning_rate, decay_steps, decay_rate, staircase=False):
     Examples:
         .. code-block:: python
 
+          import paddle.fluid as fluid
           base_lr = 0.1
           sgd_optimizer = fluid.optimizer.SGD(
-                learning_rate=fluid.layers.exponential_decay(
-                    learning_rate=base_lr,
-                    decay_steps=10000,
-                    decay_rate=0.5,
-                    staircase=True))
-          sgd_optimizer.minimize(avg_cost)
+	      learning_rate=fluid.layers.exponential_decay(
+		    learning_rate=base_lr,
+		    decay_steps=10000,
+		    decay_rate=0.5,
+		    staircase=True))
 
     """
     with default_main_program()._lr_schedule_guard():
@@ -167,6 +167,19 @@ def natural_exp_decay(learning_rate, decay_steps, decay_rate, staircase=False):
 
     Returns:
         The decayed learning rate
+
+    Examples:
+        .. code-block:: python
+
+          import paddle.fluid as fluid
+          base_lr = 0.1
+          sgd_optimizer = fluid.optimizer.SGD(
+	      learning_rate=fluid.layers.natural_exp_decay(
+		    learning_rate=base_lr,
+		    decay_steps=10000,
+		    decay_rate=0.5,
+		    staircase=True))
+
     """
     with default_main_program()._lr_schedule_guard():
         if imperative_base.enabled():
@@ -210,14 +223,14 @@ def inverse_time_decay(learning_rate, decay_steps, decay_rate, staircase=False):
     Examples:
         .. code-block:: python
 
+          import paddle.fluid as fluid
           base_lr = 0.1
           sgd_optimizer = fluid.optimizer.SGD(
-                learning_rate=fluid.layers.inverse_time_decay(
-                    learning_rate=base_lr,
-                    decay_steps=10000,
-                    decay_rate=0.5,
-                    staircase=True))
-          sgd_optimizer.minimize(avg_cost)
+	      learning_rate=fluid.layers.natural_exp_decay(
+		    learning_rate=base_lr,
+		    decay_steps=10000,
+		    decay_rate=0.5,
+		    staircase=True))
     """
     with default_main_program()._lr_schedule_guard():
         if imperative_base.enabled():

python/paddle/fluid/layers/nn.py

@@ -2930,9 +2930,12 @@ def adaptive_pool3d(input,
           #                 output[:, :, i, j, k] =
           #                     avg(input[:, :, dstart:dend, hstart: hend, wstart: wend])
           #
+
+          import paddle.fluid as fluid
+
           data = fluid.layers.data(
-              name='data', shape=[3, 32, 32], dtype='float32')
-          pool_out, mask = fluid.layers.adaptive_pool3d(
+              name='data', shape=[3, 32, 32, 32], dtype='float32')
+          pool_out = fluid.layers.adaptive_pool3d(
                             input=data,
                             pool_size=[3, 3, 3],
                             pool_type='avg')
@@ -3525,10 +3528,13 @@ def spectral_norm(weight, dim=0, power_iters=1, eps=1e-12, name=None):
         Variable: A tensor variable of weight parameters after spectral normalization.
 
     Examples:
+       .. code-block:: python
 
-        >>> weight = fluid.layers.data(name='weight', shape=[8, 32, 32],
-        >>>                          dtype='float32')
-        >>> x = fluid.layers.spectral_norm(weight=data, dim=1, power_iters=2)
+            import paddle.fluid as fluid
+
+            weight = fluid.layers.data(name='weight', shape=[2, 8, 32, 32], 
+                                       append_batch_size=False, dtype='float32')
+            x = fluid.layers.spectral_norm(weight=weight, dim=1, power_iters=2)
     """
     helper = LayerHelper('spectral_norm', **locals())
     dtype = weight.dtype
@@ -10398,9 +10404,11 @@ def grid_sampler(x, grid, name=None):
 
         .. code-block:: python
 
-            x = fluid.layers.data(name='x', shape=[3, 10, 32, 32], dtype='float32')
-            theta = fluid.layers.data(name='theta', shape=[3, 2, 3], dtype='float32')
-            grid = fluid.layers.affine_grid(input=theta, size=[3, 10, 32, 32]})
+            import paddle.fluid as fluid
+
+            x = fluid.layers.data(name='x', shape=[10, 32, 32], dtype='float32')
+            theta = fluid.layers.data(name='theta', shape=[2, 3], dtype='float32')
+            grid = fluid.layers.affine_grid(theta=theta, out_shape=[3, 10, 32, 32])
             out = fluid.layers.grid_sampler(x=x, grid=grid)
 
     """