core: Put Python version as a project requirement so it is considered…

… by ruff (langchain-ai#26608)

Ruff doesn't know about the python version in
`[tool.poetry.dependencies]`. It can get it from
`project.requires-python`.

Notes:
* poetry seems to have issues getting the python constraints from
`requires-python` and using `python` in per dependency constraints. So I
had to duplicate the info. I will open an issue on poetry.
* `inspect.isclass()` doesn't work correctly with `GenericAlias`
(`list[...]`, `dict[..., ...]`) on Python <3.11 so I added some `not
isinstance(type, GenericAlias)` checks:

Python 3.11
```pycon
>>> import inspect
>>> inspect.isclass(list)
True
>>> inspect.isclass(list[str])
False
```

Python 3.9
```pycon
>>> import inspect
>>> inspect.isclass(list)
True
>>> inspect.isclass(list[str])
True
```

Co-authored-by: Eugene Yurtsev <[email protected]>

libs/core/langchain_core/_api/beta_decorator.py

@@ -14,7 +14,8 @@
 import functools
 import inspect
 import warnings
-from typing import Any, Callable, Generator, Type, TypeVar, Union, cast
+from collections.abc import Generator
+from typing import Any, Callable, TypeVar, Union, cast
 
 from langchain_core._api.internal import is_caller_internal
 
@@ -26,7 +27,7 @@ class LangChainBetaWarning(DeprecationWarning):
 # PUBLIC API
 
 
-T = TypeVar("T", bound=Union[Callable[..., Any], Type])
+T = TypeVar("T", bound=Union[Callable[..., Any], type])
 
 
 def beta(

libs/core/langchain_core/_api/deprecation.py

@@ -14,11 +14,10 @@
 import functools
 import inspect
 import warnings
+from collections.abc import Generator
 from typing import (
     Any,
     Callable,
-    Generator,
-    Type,
     TypeVar,
     Union,
     cast,
@@ -41,7 +40,7 @@ class LangChainPendingDeprecationWarning(PendingDeprecationWarning):
 
 
 # Last Any should be FieldInfoV1 but this leads to circular imports
-T = TypeVar("T", bound=Union[Type, Callable[..., Any], Any])
+T = TypeVar("T", bound=Union[type, Callable[..., Any], Any])
 
 
 def _validate_deprecation_params(
@@ -262,7 +261,7 @@ def finalize(wrapper: Callable[..., Any], new_doc: str) -> T:
             if not _obj_type:
                 _obj_type = "attribute"
             wrapped = None
-            _name = _name or cast(Union[Type, Callable], obj.fget).__qualname__
+            _name = _name or cast(Union[type, Callable], obj.fget).__qualname__
             old_doc = obj.__doc__
 
             class _deprecated_property(property):
@@ -304,7 +303,7 @@ def finalize(wrapper: Callable[..., Any], new_doc: str) -> T:
                 )
 
         else:
-            _name = _name or cast(Union[Type, Callable], obj).__qualname__
+            _name = _name or cast(Union[type, Callable], obj).__qualname__
             if not _obj_type:
                 # edge case: when a function is within another function
                 # within a test, this will call it a "method" not a "function"

libs/core/langchain_core/agents.py

@@ -25,7 +25,8 @@
 from __future__ import annotations
 
 import json
-from typing import Any, Literal, Sequence, Union
+from collections.abc import Sequence
+from typing import Any, Literal, Union
 
 from langchain_core.load.serializable import Serializable
 from langchain_core.messages import (

libs/core/langchain_core/beta/runnables/context.py

@@ -1,19 +1,13 @@
 import asyncio
 import threading
 from collections import defaultdict
+from collections.abc import Awaitable, Mapping, Sequence
 from functools import partial
 from itertools import groupby
 from typing import (
     Any,
-    Awaitable,
     Callable,
-    DefaultDict,
-    Dict,
-    List,
-    Mapping,
     Optional,
-    Sequence,
-    Type,
     TypeVar,
     Union,
 )
@@ -30,7 +24,7 @@
 from langchain_core.runnables.utils import ConfigurableFieldSpec, Input, Output
 
 T = TypeVar("T")
-Values = Dict[Union[asyncio.Event, threading.Event], Any]
+Values = dict[Union[asyncio.Event, threading.Event], Any]
 CONTEXT_CONFIG_PREFIX = "__context__/"
 CONTEXT_CONFIG_SUFFIX_GET = "/get"
 CONTEXT_CONFIG_SUFFIX_SET = "/set"
@@ -70,10 +64,10 @@ def _key_from_id(id_: str) -> str:
 
 def _config_with_context(
     config: RunnableConfig,
-    steps: List[Runnable],
+    steps: list[Runnable],
     setter: Callable,
     getter: Callable,
-    event_cls: Union[Type[threading.Event], Type[asyncio.Event]],
+    event_cls: Union[type[threading.Event], type[asyncio.Event]],
 ) -> RunnableConfig:
     if any(k.startswith(CONTEXT_CONFIG_PREFIX) for k in config.get("configurable", {})):
         return config
@@ -99,10 +93,10 @@ def _config_with_context(
     }
 
     values: Values = {}
-    events: DefaultDict[str, Union[asyncio.Event, threading.Event]] = defaultdict(
+    events: defaultdict[str, Union[asyncio.Event, threading.Event]] = defaultdict(
         event_cls
     )
-    context_funcs: Dict[str, Callable[[], Any]] = {}
+    context_funcs: dict[str, Callable[[], Any]] = {}
     for key, group in grouped_by_key.items():
         getters = [s for s in group if s[0].id.endswith(CONTEXT_CONFIG_SUFFIX_GET)]
         setters = [s for s in group if s[0].id.endswith(CONTEXT_CONFIG_SUFFIX_SET)]
@@ -129,7 +123,7 @@ def _config_with_context(
 
 def aconfig_with_context(
     config: RunnableConfig,
-    steps: List[Runnable],
+    steps: list[Runnable],
 ) -> RunnableConfig:
     """Asynchronously patch a runnable config with context getters and setters.
 
@@ -145,7 +139,7 @@ def aconfig_with_context(
 
 def config_with_context(
     config: RunnableConfig,
-    steps: List[Runnable],
+    steps: list[Runnable],
 ) -> RunnableConfig:
     """Patch a runnable config with context getters and setters.
 
@@ -165,13 +159,13 @@ class ContextGet(RunnableSerializable):
 
     prefix: str = ""
 
-    key: Union[str, List[str]]
+    key: Union[str, list[str]]
 
     def __str__(self) -> str:
         return f"ContextGet({_print_keys(self.key)})"
 
     @property
-    def ids(self) -> List[str]:
+    def ids(self) -> list[str]:
         prefix = self.prefix + "/" if self.prefix else ""
         keys = self.key if isinstance(self.key, list) else [self.key]
         return [
@@ -180,7 +174,7 @@ def ids(self) -> List[str]:
         ]
 
     @property
-    def config_specs(self) -> List[ConfigurableFieldSpec]:
+    def config_specs(self) -> list[ConfigurableFieldSpec]:
         return super().config_specs + [
             ConfigurableFieldSpec(
                 id=id_,
@@ -256,15 +250,15 @@ def __str__(self) -> str:
         return f"ContextSet({_print_keys(list(self.keys.keys()))})"
 
     @property
-    def ids(self) -> List[str]:
+    def ids(self) -> list[str]:
         prefix = self.prefix + "/" if self.prefix else ""
         return [
             f"{CONTEXT_CONFIG_PREFIX}{prefix}{key}{CONTEXT_CONFIG_SUFFIX_SET}"
             for key in self.keys
         ]
 
     @property
-    def config_specs(self) -> List[ConfigurableFieldSpec]:
+    def config_specs(self) -> list[ConfigurableFieldSpec]:
         mapper_config_specs = [
             s
             for mapper in self.keys.values()
@@ -364,7 +358,7 @@ def create_scope(scope: str, /) -> "PrefixContext":
         return PrefixContext(prefix=scope)
 
     @staticmethod
-    def getter(key: Union[str, List[str]], /) -> ContextGet:
+    def getter(key: Union[str, list[str]], /) -> ContextGet:
         return ContextGet(key=key)
 
     @staticmethod
@@ -385,7 +379,7 @@ class PrefixContext:
     def __init__(self, prefix: str = ""):
         self.prefix = prefix
 
-    def getter(self, key: Union[str, List[str]], /) -> ContextGet:
+    def getter(self, key: Union[str, list[str]], /) -> ContextGet:
         return ContextGet(key=key, prefix=self.prefix)
 
     def setter(

libs/core/langchain_core/caches.py

@@ -23,7 +23,8 @@
 from __future__ import annotations
 
 from abc import ABC, abstractmethod
-from typing import Any, Optional, Sequence
+from collections.abc import Sequence
+from typing import Any, Optional
 
 from langchain_core.outputs import Generation
 from langchain_core.runnables import run_in_executor

libs/core/langchain_core/callbacks/base.py

@@ -3,7 +3,8 @@
 from __future__ import annotations
 
 import logging
-from typing import TYPE_CHECKING, Any, List, Optional, Sequence, TypeVar, Union
+from collections.abc import Sequence
+from typing import TYPE_CHECKING, Any, Optional, TypeVar, Union
 from uuid import UUID
 
 from tenacity import RetryCallState
@@ -1070,4 +1071,4 @@ def remove_metadata(self, keys: list[str]) -> None:
             self.inheritable_metadata.pop(key)
 
 
-Callbacks = Optional[Union[List[BaseCallbackHandler], BaseCallbackManager]]
+Callbacks = Optional[Union[list[BaseCallbackHandler], BaseCallbackManager]]

libs/core/langchain_core/callbacks/manager.py

@@ -5,19 +5,15 @@
 import logging
 import uuid
 from abc import ABC, abstractmethod
+from collections.abc import AsyncGenerator, Coroutine, Generator, Sequence
 from concurrent.futures import ThreadPoolExecutor
 from contextlib import asynccontextmanager, contextmanager
 from contextvars import copy_context
 from typing import (
     TYPE_CHECKING,
     Any,
-    AsyncGenerator,
     Callable,
-    Coroutine,
-    Generator,
     Optional,
-    Sequence,
-    Type,
     TypeVar,
     Union,
     cast,
@@ -2352,7 +2348,7 @@ def _configure(
             and handler_class is not None
         )
         if var.get() is not None or create_one:
-            var_handler = var.get() or cast(Type[BaseCallbackHandler], handler_class)()
+            var_handler = var.get() or cast(type[BaseCallbackHandler], handler_class)()
             if handler_class is None:
                 if not any(
                     handler is var_handler  # direct pointer comparison

libs/core/langchain_core/chat_history.py

@@ -18,7 +18,8 @@
 from __future__ import annotations
 
 from abc import ABC, abstractmethod
-from typing import Sequence, Union
+from collections.abc import Sequence
+from typing import Union
 
 from pydantic import BaseModel, Field
 

libs/core/langchain_core/chat_loaders.py

@@ -1,5 +1,5 @@
 from abc import ABC, abstractmethod
-from typing import Iterator, List
+from collections.abc import Iterator
 
 from langchain_core.chat_sessions import ChatSession
 
@@ -15,7 +15,7 @@ def lazy_load(self) -> Iterator[ChatSession]:
             An iterator of chat sessions.
         """
 
-    def load(self) -> List[ChatSession]:
+    def load(self) -> list[ChatSession]:
         """Eagerly load the chat sessions into memory.
 
         Returns:

libs/core/langchain_core/chat_sessions.py

@@ -1,6 +1,7 @@
 """**Chat Sessions** are a collection of messages and function calls."""
 
-from typing import Sequence, TypedDict
+from collections.abc import Sequence
+from typing import TypedDict
 
 from langchain_core.messages import BaseMessage
 

libs/core/langchain_core/document_loaders/base.py

@@ -3,7 +3,8 @@
 from __future__ import annotations
 
 from abc import ABC, abstractmethod
-from typing import TYPE_CHECKING, AsyncIterator, Iterator, Optional
+from collections.abc import AsyncIterator, Iterator
+from typing import TYPE_CHECKING, Optional
 
 from langchain_core.documents import Document
 from langchain_core.runnables import run_in_executor

libs/core/langchain_core/document_loaders/blob_loaders.py

@@ -8,7 +8,7 @@
 from __future__ import annotations
 
 from abc import ABC, abstractmethod
-from typing import Iterable
+from collections.abc import Iterable
 
 # Re-export Blob and PathLike for backwards compatibility
 from langchain_core.documents.base import Blob as Blob

libs/core/langchain_core/document_loaders/langsmith.py

@@ -1,7 +1,8 @@
 import datetime
 import json
 import uuid
-from typing import Any, Callable, Iterator, Optional, Sequence, Union
+from collections.abc import Iterator, Sequence
+from typing import Any, Callable, Optional, Union
 
 from langsmith import Client as LangSmithClient
 

libs/core/langchain_core/documents/base.py

@@ -2,9 +2,10 @@
 
 import contextlib
 import mimetypes
+from collections.abc import Generator
 from io import BufferedReader, BytesIO
 from pathlib import PurePath
-from typing import Any, Generator, Literal, Optional, Union, cast
+from typing import Any, Literal, Optional, Union, cast
 
 from pydantic import ConfigDict, Field, field_validator, model_validator
 

libs/core/langchain_core/documents/compressor.py

@@ -1,7 +1,8 @@
 from __future__ import annotations
 
 from abc import ABC, abstractmethod
-from typing import Optional, Sequence
+from collections.abc import Sequence
+from typing import Optional
 
 from pydantic import BaseModel
 

libs/core/langchain_core/documents/transformers.py

@@ -1,7 +1,8 @@
 from __future__ import annotations
 
 from abc import ABC, abstractmethod
-from typing import TYPE_CHECKING, Any, Sequence
+from collections.abc import Sequence
+from typing import TYPE_CHECKING, Any
 
 from langchain_core.runnables.config import run_in_executor
 

libs/core/langchain_core/embeddings/embeddings.py

@@ -1,7 +1,6 @@
 """**Embeddings** interface."""
 
 from abc import ABC, abstractmethod
-from typing import List
 
 from langchain_core.runnables.config import run_in_executor
 
@@ -35,7 +34,7 @@ class Embeddings(ABC):
     """
 
     @abstractmethod
-    def embed_documents(self, texts: List[str]) -> List[List[float]]:
+    def embed_documents(self, texts: list[str]) -> list[list[float]]:
         """Embed search docs.
 
         Args:
@@ -46,7 +45,7 @@ def embed_documents(self, texts: List[str]) -> List[List[float]]:
         """
 
     @abstractmethod
-    def embed_query(self, text: str) -> List[float]:
+    def embed_query(self, text: str) -> list[float]:
         """Embed query text.
 
         Args:
@@ -56,7 +55,7 @@ def embed_query(self, text: str) -> List[float]:
             Embedding.
         """
 
-    async def aembed_documents(self, texts: List[str]) -> List[List[float]]:
+    async def aembed_documents(self, texts: list[str]) -> list[list[float]]:
         """Asynchronous Embed search docs.
 
         Args:
@@ -67,7 +66,7 @@ async def aembed_documents(self, texts: List[str]) -> List[List[float]]:
         """
         return await run_in_executor(None, self.embed_documents, texts)
 
-    async def aembed_query(self, text: str) -> List[float]:
+    async def aembed_query(self, text: str) -> list[float]:
         """Asynchronous Embed query text.
 
         Args: