chore: import upstream snapshot with attribution

python/paddle/_typing/basic.py

@@ -0,0 +1,66 @@
+# Copyright (c) 2024 PaddlePaddle Authors. All Rights Reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+from __future__ import annotations
+
+from collections.abc import Sequence
+from types import EllipsisType
+from typing import (
+    TYPE_CHECKING,
+    Any,
+    TypeAlias,
+    TypeVar,
+    Union,
+)
+
+import numpy as np
+import numpy.typing as npt
+from typing_extensions import Never
+
+if TYPE_CHECKING:
+    from paddle import ParamAttr, Tensor
+    from paddle.nn.initializer import Initializer
+    from paddle.regularizer import WeightDecayRegularizer
+
+
+Numeric: TypeAlias = Union[int, float, bool, complex, np.number, "Tensor"]
+TensorLike: TypeAlias = Union[npt.NDArray[Any], "Tensor", Numeric]
+_TensorIndexItem: TypeAlias = Union[
+    None, bool, int, slice, "Tensor", EllipsisType
+]
+TensorIndex: TypeAlias = (
+    _TensorIndexItem | tuple[_TensorIndexItem, ...] | list[_TensorIndexItem]
+)
+
+
+_T = TypeVar("_T")
+
+NestedSequence = _T | Sequence["NestedSequence[_T]"]
+NestedList = _T | list["NestedList[_T]"]
+NestedStructure = (
+    _T | dict[str, "NestedStructure[_T]"] | Sequence["NestedStructure[_T]"]
+)
+NumericSequence = Sequence[Numeric]
+NestedNumericSequence: TypeAlias = NestedSequence[Numeric]
+TensorOrTensors: TypeAlias = Union["Tensor", Sequence["Tensor"]]
+
+ParamAttrLike: TypeAlias = Union[
+    "ParamAttr", "Initializer", "WeightDecayRegularizer", str, bool
+]
+
+
+def unreached() -> Never:
+    """Mark a code path as unreachable.
+    Refer to https://typing.readthedocs.io/en/latest/source/unreachable.html#marking-code-as-unreachable
+    """
+    raise RuntimeError("Unreachable code path")