[legacy] move communication and nn to legacy and refactor logger (#4671)

* [legacy] move communication to legacy (#4640)

* [legacy] refactor logger and clean up legacy codes (#4654)

* [legacy] make logger independent to gpc

* [legacy] make optim independent to registry

* [legacy] move test engine to legacy

* [legacy] move nn to legacy (#4656)

* [legacy] move nn to legacy

* [checkpointio] fix save hf config

* [test] remove useledd rpc pp test

* [legacy] fix nn init

* [example] skip tutorial hybriad parallel example

* [devops] test doc check

* [devops] test doc check

colossalai/legacy/engine/schedule/_pipeline_schedule.py

@@ -6,7 +6,7 @@ from typing import Callable, List, Tuple, Union
 
 import torch.cuda
 
-import colossalai.communication as comm
+import colossalai.legacy.communication as comm
 from colossalai.amp.naive_amp import NaiveAMPModel
 from colossalai.context.parallel_mode import ParallelMode
 from colossalai.core import global_context as gpc

colossalai/legacy/engine/schedule/_pipeline_schedule_v2.py

@@ -5,10 +5,10 @@ from typing import Iterable, Tuple
 
 import torch.cuda
 
-import colossalai.communication.p2p_v2 as comm
-from colossalai import engine
+import colossalai.legacy.communication.p2p_v2 as comm
 from colossalai.context.parallel_mode import ParallelMode
 from colossalai.core import global_context as gpc
+from colossalai.legacy.engine import Engine
 from colossalai.utils.cuda import get_current_device
 
 from ._pipeline_schedule import PipelineSchedule
@@ -60,7 +60,7 @@ class PipelineScheduleV2(PipelineSchedule):
     """
 
     def forward_backward_step(self,
-                              engine: engine.Engine,
+                              engine: Engine,
                               data_iter: Iterable,
                               forward_only=False,
                               return_loss=True,