multiple: pydantic 2 compatibility, v0.3 (#26443)

Signed-off-by: ChengZi <chen.zhang@zilliz.com>
Co-authored-by: Eugene Yurtsev <eyurtsev@gmail.com>
Co-authored-by: Bagatur <22008038+baskaryan@users.noreply.github.com>
Co-authored-by: Dan O'Donovan <dan.odonovan@gmail.com>
Co-authored-by: Tom Daniel Grande <tomdgrande@gmail.com>
Co-authored-by: Grande <Tom.Daniel.Grande@statsbygg.no>
Co-authored-by: Bagatur <baskaryan@gmail.com>
Co-authored-by: ccurme <chester.curme@gmail.com>
Co-authored-by: Harrison Chase <hw.chase.17@gmail.com>
Co-authored-by: Tomaz Bratanic <bratanic.tomaz@gmail.com>
Co-authored-by: ZhangShenao <15201440436@163.com>
Co-authored-by: Friso H. Kingma <fhkingma@gmail.com>
Co-authored-by: ChengZi <chen.zhang@zilliz.com>
Co-authored-by: Nuno Campos <nuno@langchain.dev>
Co-authored-by: Morgante Pell <morgantep@google.com>

libs/community/langchain_community/cross_encoders/huggingface.py

@@ -1,6 +1,6 @@
 from typing import Any, Dict, List, Tuple
 
-from langchain_core.pydantic_v1 import BaseModel, Field
+from pydantic import BaseModel, ConfigDict, Field
 
 from langchain_community.cross_encoders.base import BaseCrossEncoder
 
@@ -23,7 +23,7 @@ class HuggingFaceCrossEncoder(BaseModel, BaseCrossEncoder):
             )
     """
 
-    client: Any  #: :meta private:
+    client: Any = None  #: :meta private:
     model_name: str = DEFAULT_MODEL_NAME
     """Model name to use."""
     model_kwargs: Dict[str, Any] = Field(default_factory=dict)
@@ -45,8 +45,7 @@ class HuggingFaceCrossEncoder(BaseModel, BaseCrossEncoder):
             self.model_name, **self.model_kwargs
         )
 
-    class Config:
-        extra = "forbid"
+    model_config = ConfigDict(extra="forbid", protected_namespaces=())
 
     def score(self, text_pairs: List[Tuple[str, str]]) -> List[float]:
         """Compute similarity scores using a HuggingFace transformer model.