[legacy] move trainer to legacy (#4545)

* [legacy] move trainer to legacy

* [doc] update docs related to trainer

* [test] ignore legacy test

colossalai/legacy/trainer/_trainer.py

@@ -1,14 +1,13 @@
-from typing import Union, List, Any
+from typing import Any, List, Union
 
 import torch
 from torch.utils.data import DataLoader
 from tqdm import tqdm
 
 from colossalai.engine import Engine
+from colossalai.legacy.trainer.hooks import BaseHook
 from colossalai.logging import DistributedLogger
-from colossalai.utils import MultiTimer
-from colossalai.utils import is_dp_rank_0, is_tp_rank_0, is_no_pp_or_last_stage
-from colossalai.trainer.hooks import BaseHook
+from colossalai.utils import MultiTimer, is_dp_rank_0, is_no_pp_or_last_stage, is_tp_rank_0
 
 
 class Trainer:

colossalai/legacy/trainer/hooks/__init__.py

@@ -1,7 +1,12 @@
 from ._base_hook import BaseHook
 from ._checkpoint_hook import SaveCheckpointHook
-from ._log_hook import (LogMemoryByEpochHook, LogMetricByEpochHook, LogMetricByStepHook, LogTimingByEpochHook,
-                        TensorboardHook)
+from ._log_hook import (
+    LogMemoryByEpochHook,
+    LogMetricByEpochHook,
+    LogMetricByStepHook,
+    LogTimingByEpochHook,
+    TensorboardHook,
+)
 from ._lr_scheduler_hook import LRSchedulerHook
 from ._metric_hook import AccuracyHook, LossHook, MetricHook, ThroughputHook
 

colossalai/legacy/trainer/hooks/_checkpoint_hook.py

@@ -1,11 +1,12 @@
 #!/usr/bin/env python
 # -*- encoding: utf-8 -*-
 import torch
-from colossalai.logging import get_dist_logger
 
+from colossalai.legacy.trainer.hooks import BaseHook
+from colossalai.logging import get_dist_logger
 from colossalai.registry import HOOKS
-from colossalai.trainer.hooks import BaseHook
 from colossalai.utils.checkpointing import save_checkpoint
+
 from ._lr_scheduler_hook import LRSchedulerHook
 
 

colossalai/legacy/trainer/hooks/_log_hook.py

@@ -3,17 +3,17 @@
 
 import os
 import os.path as osp
-
 from typing import List
+
 from colossalai.context import ParallelMode
 from colossalai.core import global_context as gpc
-from colossalai.registry import HOOKS
+from colossalai.legacy.trainer.hooks._metric_hook import ThroughputMetric
 from colossalai.logging import DistributedLogger
-from colossalai.utils import report_memory_usage, is_dp_rank_0, \
-    is_tp_rank_0, is_no_pp_or_last_stage, MultiTimer
+from colossalai.registry import HOOKS
+from colossalai.utils import MultiTimer, is_dp_rank_0, is_no_pp_or_last_stage, is_tp_rank_0, report_memory_usage
+
 from ._base_hook import BaseHook
 from ._commons_ import _format_number
-from colossalai.trainer.hooks._metric_hook import ThroughputMetric
 
 
 class LogByEpochHook(BaseHook):

colossalai/legacy/trainer/hooks/_lr_scheduler_hook.py

@@ -1,6 +1,7 @@
-from colossalai.registry import HOOKS
 from torch import Tensor
 
+from colossalai.registry import HOOKS
+
 from ._metric_hook import LearningRateMetric, MetricHook
 
 

colossalai/legacy/trainer/hooks/_metric_hook.py

@@ -6,6 +6,7 @@ from typing import Callable
 
 import torch
 import torch.distributed as dist
+
 from colossalai.communication import all_reduce
 from colossalai.context import ParallelMode
 from colossalai.core import global_context as gpc
@@ -19,8 +20,8 @@ from ._commons_ import _format_number
 class Metric(ABC):
     """A basic class of metric collectors. It collects a specific
     metric during training or evaluation and would always be used with
-    :class:`MetricHook` to help it update its states and show the 
-    metric. So please use corresponding hook class to make the metric 
+    :class:`MetricHook` to help it update its states and show the
+    metric. So please use corresponding hook class to make the metric
     collector works.
 
     Args:
@@ -220,9 +221,9 @@ class AccuracyMetric(Metric):
 
 
 class MetricHook(BaseHook):
-    """Specialized hook classes for :class:`Metric`. 
-    Some help metric collectors initialize, reset and 
-    update their states. Others are used to display and 
+    """Specialized hook classes for :class:`Metric`.
+    Some help metric collectors initialize, reset and
+    update their states. Others are used to display and
     record the metric.
 
     Args: