diff --git a/src/handyllm/_io.py b/src/handyllm/_io.py
new file mode 100644
index 0000000..fa30cdd
--- /dev/null
+++ b/src/handyllm/_io.py
@@ -0,0 +1,55 @@
+import json
+from pathlib import Path
+import yaml
+from functools import wraps
+
+from .response import DictProxy
+
+
+# add multi representer for Path, for YAML serialization
+class MySafeDumper(yaml.SafeDumper):
+    pass
+
+
+MySafeDumper.add_multi_representer(
+    Path, lambda dumper, data: dumper.represent_str(str(data))
+)
+MySafeDumper.add_multi_representer(
+    DictProxy, lambda dumper, data: dumper.represent_dict(data)
+)
+
+
+@wraps(yaml.dump)
+def yaml_dump(*args, **kwargs):
+    kwargs.setdefault("Dumper", MySafeDumper)
+    kwargs.setdefault("allow_unicode", True)
+    return yaml.dump(*args, **kwargs)
+
+
+@wraps(yaml.safe_load)
+def yaml_load(*args, **kwargs):
+    return yaml.safe_load(*args, **kwargs)
+
+
+@wraps(json.dump)
+def json_dump(*args, **kwargs):
+    kwargs.setdefault("ensure_ascii", False)
+    kwargs.setdefault("indent", 2)
+    return json.dump(*args, **kwargs)
+
+
+@wraps(json.dumps)
+def json_dumps(*args, **kwargs):
+    kwargs.setdefault("ensure_ascii", False)
+    kwargs.setdefault("indent", 2)
+    return json.dumps(*args, **kwargs)
+
+
+@wraps(json.load)
+def json_load(*args, **kwargs):
+    return json.load(*args, **kwargs)
+
+
+@wraps(json.loads)
+def json_loads(*args, **kwargs):
+    return json.loads(*args, **kwargs)
diff --git a/src/handyllm/_utils.py b/src/handyllm/_utils.py
index 887e4e7..6629eb5 100644
--- a/src/handyllm/_utils.py
+++ b/src/handyllm/_utils.py
@@ -1,12 +1,12 @@
 import collections.abc
 import copy
-import json
 from urllib.parse import quote_plus
 import time
 import inspect
 
 from ._constants import API_TYPES_AZURE
 from .prompt_converter import PromptConverter
+from ._io import json_dumps
 
 
 def get_request_url(request_url, api_type, api_version, engine):
@@ -41,7 +41,7 @@ def wrap_log_input(input_content: str, log_marks, kwargs):
         input_lines = [str(item) for item in log_marks]
     else:
         input_lines = [str(log_marks)]
-    input_lines.append(json.dumps(arguments, indent=2, ensure_ascii=False))
+    input_lines.append(json_dumps(arguments, indent=2, ensure_ascii=False))
     input_lines.append(" INPUT START ".center(50, "-"))
     input_lines.append(input_content)
     input_lines.append(" INPUT END ".center(50, "-") + "\n")
diff --git a/src/handyllm/cache_manager.py b/src/handyllm/cache_manager.py
index bec53bf..501e5d8 100644
--- a/src/handyllm/cache_manager.py
+++ b/src/handyllm/cache_manager.py
@@ -2,23 +2,22 @@
 
 from functools import wraps
 from inspect import iscoroutinefunction
-import json
 from os import PathLike
 from pathlib import Path
 from typing import Callable, Collection, Iterable, List, Optional, TypeVar, Union, cast
 from typing_extensions import ParamSpec
-import yaml
 
 from .types import PathType, StrHandler, StringifyHandler
+from ._io import json_load, json_dump, yaml_load, yaml_dump
 
 
 def _suffix_loader(file: Path):
     with open(file, "r", encoding="utf-8") as f:
         # determine the format according to the file suffix
         if file.suffix.endswith(".yaml") or file.suffix.endswith(".yml"):
-            content = yaml.safe_load(f)
+            content = yaml_load(f)
         elif file.suffix.endswith(".json"):
-            content = json.load(f)
+            content = json_load(f)
         else:
             content = f.read()
         return content
@@ -28,9 +27,9 @@ def _suffix_dumper(file: Path, content):
     with open(file, "w", encoding="utf-8") as f:
         # determine the format according to the file suffix
         if file.suffix.endswith(".yaml") or file.suffix.endswith(".yml"):
-            yaml.dump(content, f, default_flow_style=False, allow_unicode=True)
+            yaml_dump(content, f, default_flow_style=False)
         elif file.suffix.endswith(".json"):
-            json.dump(content, f, ensure_ascii=False, indent=2)
+            json_dump(content, f)
         else:
             f.write(str(content))
 
diff --git a/src/handyllm/endpoint_manager.py b/src/handyllm/endpoint_manager.py
index 034a3fb..b9e0cc4 100644
--- a/src/handyllm/endpoint_manager.py
+++ b/src/handyllm/endpoint_manager.py
@@ -6,10 +6,10 @@
 from threading import Lock
 from collections.abc import MutableSequence
 from typing import Iterable, Mapping, Optional, Union
-import yaml
 
 from .types import PathType
 from ._utils import isiterable
+from ._io import yaml_load
 
 
 class Endpoint:
@@ -124,7 +124,7 @@ def load_from_list(self, obj: Iterable[Union[Mapping, Endpoint]], override=False
 
     def load_from(self, path: PathType, encoding="utf-8", override=False):
         with open(path, "r", encoding=encoding) as fin:
-            obj = yaml.safe_load(fin)
+            obj = yaml_load(fin)
         if isinstance(obj, Mapping):
             obj = obj.get("endpoints", None)
         if obj:
diff --git a/src/handyllm/hprompt.py b/src/handyllm/hprompt.py
index ccda4e9..0729bcd 100644
--- a/src/handyllm/hprompt.py
+++ b/src/handyllm/hprompt.py
@@ -17,7 +17,6 @@
 ]
 
 import inspect
-import json
 import re
 import copy
 import io
@@ -41,7 +40,6 @@
 from abc import abstractmethod, ABC
 from contextlib import asynccontextmanager, contextmanager
 
-import yaml
 import frontmatter
 from mergedeep import merge as merge_dict, Strategy
 from dotenv import load_dotenv
@@ -60,6 +58,7 @@
 from .run_config import RunConfig, RecordRequestMode, CredentialType, VarMapFileFormat
 from .types import PathType, SyncHandlerChat, SyncHandlerCompletions, VarMapType
 from .response import ChatChunk, ChatResponse, CompletionsChunk, CompletionsResponse
+from ._io import MySafeDumper, json_load, yaml_load
 
 
 PromptType = TypeVar("PromptType", bound="HandyPrompt")
@@ -71,15 +70,6 @@
 handler = frontmatter.YAMLHandler()
 
 
-# add multi representer for Path, for YAML serialization
-class MySafeDumper(yaml.SafeDumper):
-    pass
-
-
-MySafeDumper.add_multi_representer(
-    Path, lambda dumper, data: dumper.represent_str(str(data))
-)
-
 p_var_map = re.compile(r"(%\w+%)")
 
 DEFAULT_CONFIG = RunConfig()
@@ -462,9 +452,9 @@ def _prepare_run(
                     evaled_run_config.credential_path, "r", encoding="utf-8"
                 ) as fin:
                     if evaled_run_config.credential_type == CredentialType.JSON:
-                        credential_dict = json.load(fin)
+                        credential_dict = json_load(fin)
                     else:
-                        credential_dict = yaml.safe_load(fin)
+                        credential_dict = yaml_load(fin)
                 # do not overwrite the existing request arguments
                 for key, value in credential_dict.items():
                     if key not in evaled_request:
@@ -1103,7 +1093,7 @@ def load_var_map(
     """
     with open(path, "r", encoding="utf-8") as fin:
         if format in (VarMapFileFormat.JSON, VarMapFileFormat.YAML):
-            return yaml.safe_load(fin)
+            return yaml_load(fin)
         content = fin.read()
     substitute_map = {}
     blocks = p_var_map.split(content)
diff --git a/src/handyllm/openai_client.py b/src/handyllm/openai_client.py
index 28f6d32..263d419 100644
--- a/src/handyllm/openai_client.py
+++ b/src/handyllm/openai_client.py
@@ -7,13 +7,11 @@
 
 from typing import Dict, Iterable, Mapping, Optional, TypeVar, Union
 import os
-import json
+from json import JSONDecodeError
 import time
 from enum import Enum, auto
 import asyncio
 
-import yaml
-
 from .endpoint_manager import Endpoint, EndpointManager
 from .requestor import (
     Requestor,
@@ -37,6 +35,7 @@
     TYPE_API_TYPES,
 )
 from .types import PathType
+from ._io import yaml_load, json_loads
 
 
 RequestorType = TypeVar("RequestorType", bound="Requestor")
@@ -145,7 +144,7 @@ def __init__(
 
     def load_from(self, path: PathType, encoding="utf-8", override=False):
         with open(path, "r", encoding=encoding) as fin:
-            obj = yaml.safe_load(fin)
+            obj = yaml_load(fin)
         if obj:
             self.load_from_obj(obj, override=override)
 
@@ -258,8 +257,8 @@ def _infer_model_engine_map(self, model_engine_map=None):
         if not json_str:
             return None
         try:
-            return json.loads(json_str)
-        except json.JSONDecodeError:
+            return json_loads(json_str)
+        except JSONDecodeError:
             return None
 
     def _consume_kwargs(self, kwargs):
diff --git a/src/handyllm/prompt_converter.py b/src/handyllm/prompt_converter.py
index c60cdb7..526c118 100644
--- a/src/handyllm/prompt_converter.py
+++ b/src/handyllm/prompt_converter.py
@@ -2,9 +2,9 @@
 
 import re
 from typing import IO, Generator, MutableMapping, MutableSequence, Optional
-import yaml
 
 from .types import PathType, ShortChatChunk
+from ._io import yaml_dump, yaml_load
 
 
 class PromptConverter:
@@ -67,11 +67,11 @@ def raw2msgs(self, raw_prompt: str):
                 if "type" in extra_properties:
                     type_of_msg = extra_properties.pop("type")
                     if type_of_msg == "tool_calls":
-                        msg["tool_calls"] = yaml.safe_load(content)
+                        msg["tool_calls"] = yaml_load(content)
                         msg["content"] = None
                     elif type_of_msg == "content_array":
                         # parse content array
-                        msg["content"] = yaml.safe_load(content)
+                        msg["content"] = yaml_load(content)
                 for key in extra_properties:
                     msg[key] = extra_properties[key]
             msgs.append(msg)
@@ -99,10 +99,10 @@ def msgs2raw(msgs):
             }
             if tool_calls:
                 extra_properties["type"] = "tool_calls"
-                content = yaml.dump(tool_calls, allow_unicode=True)
+                content = yaml_dump(tool_calls)
             elif isinstance(content, MutableSequence):
                 extra_properties["type"] = "content_array"
-                content = yaml.dump(content, allow_unicode=True)
+                content = yaml_dump(content)
             if extra_properties:
                 extra = (
                     " {"
@@ -136,7 +136,7 @@ def consume_stream2fd(
                     fd.write(' {type="tool_calls"}\n')
                     role_completed = True
                 # dump tool calls
-                fd.write(yaml.dump([tool_call], allow_unicode=True))
+                fd.write(yaml_dump([tool_call]))
             elif text:
                 if not role_completed:
                     fd.write("\n")
diff --git a/src/handyllm/requestor.py b/src/handyllm/requestor.py
index 5e42126..4d3f57c 100644
--- a/src/handyllm/requestor.py
+++ b/src/handyllm/requestor.py
@@ -20,7 +20,6 @@
 )
 import asyncio
 import logging
-import json
 import time
 import requests
 import httpx
@@ -33,6 +32,7 @@
     ChatResponse,
     CompletionsResponse,
 )
+from ._io import json_loads
 
 
 module_logger = logging.getLogger(__name__)
@@ -272,7 +272,7 @@ def _gen_stream_response(self, raw_response: requests.Response, prepare_ret):
                             return
                         if byte_line.startswith(b"data: "):
                             line = byte_line[len(b"data: ") :].decode("utf-8")
-                            yield json.loads(line)
+                            yield json_loads(line)
             except Exception as e:
                 if self._exception_callback:
                     self._exception_callback(e, prepare_ret)
@@ -393,7 +393,7 @@ async def _agen_stream_response(self, raw_response: httpx.Response, prepare_ret)
                         return
                     if raw_line.startswith("data: "):
                         line = raw_line[len("data: ") :]
-                        yield json.loads(line)
+                        yield json_loads(line)
         except Exception as e:
             if self._exception_callback:
                 self._exception_callback(e, prepare_ret)
diff --git a/src/handyllm/response.py b/src/handyllm/response.py
index 1d3e861..8c2f346 100644
--- a/src/handyllm/response.py
+++ b/src/handyllm/response.py
@@ -22,7 +22,9 @@ def __init__(self, *args, **kwargs):
             self[key] = self._wrap(value)
 
     def __getattr__(self, attr):
-        return self[attr]
+        if attr in self:
+            return self[attr]
+        raise AttributeError(f"Attribute {attr} not found")
 
     def __setattr__(self, attr, value):
         self[attr] = self._wrap(value)