[legacy] clean up legacy code (#4743)

* [legacy] remove outdated codes of pipeline (#4692)

* [legacy] remove cli of benchmark and update optim (#4690)

* [legacy] remove cli of benchmark and update optim

* [doc] fix cli doc test

* [legacy] fix engine clip grad norm

* [legacy] remove outdated colo tensor (#4694)

* [legacy] remove outdated colo tensor

* [test] fix test import

* [legacy] move outdated zero to legacy (#4696)

* [legacy] clean up utils (#4700)

* [legacy] clean up utils

* [example] update examples

* [legacy] clean up amp

* [legacy] fix amp module

* [legacy] clean up gpc (#4742)

* [legacy] clean up context

* [legacy] clean core, constants and global vars

* [legacy] refactor initialize

* [example] fix examples ci

* [example] fix examples ci

* [legacy] fix tests

* [example] fix gpt example

* [example] fix examples ci

* [devops] fix ci installation

* [example] fix examples ci

colossalai/legacy/tensor/tensor_spec.py

@@ -0,0 +1,20 @@
+from dataclasses import dataclass
+from typing import Optional
+
+from colossalai.legacy.tensor.distspec import DistPlacementPattern, _DistSpec
+from colossalai.legacy.tensor.process_group import ProcessGroup
+
+from .compute_spec import ComputeSpec
+
+
+@dataclass
+class ColoTensorSpec:
+    """ ColoTensorSpec
+
+    A data class for specifications of the `ColoTensor`.
+    It contains attributes of `ProcessGroup`, `_DistSpec`, `ComputeSpec`.
+    The latter two attributes are optional. If not set, they are default value is `Replicate()` and `None`.
+    """
+    pg: ProcessGroup
+    dist_attr: Optional[_DistSpec] = _DistSpec(DistPlacementPattern.REPLICATE)
+    compute_attr: Optional[ComputeSpec] = None