chore: 添加虚拟环境到仓库

- 添加 backend_service/venv 虚拟环境
- 包含所有Python依赖包
- 注意：虚拟环境约393MB，包含12655个文件

backend_service/venv/lib/python3.13/site-packages/cached_property.py

@@ -0,0 +1,146 @@
+__author__ = "Daniel Roy Greenfeld"
+__email__ = "daniel@feldroy.com"
+__version__ = "2.0.1"
+__license__ = "BSD"
+
+from functools import wraps
+from time import time
+import threading
+import asyncio
+
+
+class cached_property:
+    """
+    A property that is only computed once per instance and then replaces itself
+    with an ordinary attribute. Deleting the attribute resets the property.
+    Source: https://github.com/bottlepy/bottle/commit/fa7733e075da0d790d809aa3d2f53071897e6f76
+    """  # noqa
+
+    def __init__(self, func):
+        self.__doc__ = getattr(func, "__doc__")
+        self.func = func
+
+    def __get__(self, obj, cls):
+        if obj is None:
+            return self
+
+        if asyncio.iscoroutinefunction(self.func):
+            return self._wrap_in_coroutine(obj)
+
+        value = obj.__dict__[self.func.__name__] = self.func(obj)
+        return value
+
+    def _wrap_in_coroutine(self, obj):
+        @wraps(obj)
+        def wrapper():
+            future = asyncio.ensure_future(self.func(obj))
+            obj.__dict__[self.func.__name__] = future
+            return future
+
+        return wrapper()
+
+
+class threaded_cached_property:
+    """
+    A cached_property version for use in environments where multiple threads
+    might concurrently try to access the property.
+    """
+
+    def __init__(self, func):
+        self.__doc__ = getattr(func, "__doc__")
+        self.func = func
+        self.lock = threading.RLock()
+
+    def __get__(self, obj, cls):
+        if obj is None:
+            return self
+
+        obj_dict = obj.__dict__
+        name = self.func.__name__
+        with self.lock:
+            try:
+                # check if the value was computed before the lock was acquired
+                return obj_dict[name]
+
+            except KeyError:
+                # if not, do the calculation and release the lock
+                return obj_dict.setdefault(name, self.func(obj))
+
+
+class cached_property_with_ttl:
+    """
+    A property that is only computed once per instance and then replaces itself
+    with an ordinary attribute. Setting the ttl to a number expresses how long
+    the property will last before being timed out.
+    """
+
+    def __init__(self, ttl=None):
+        if callable(ttl):
+            func = ttl
+            ttl = None
+        else:
+            func = None
+        self.ttl = ttl
+        self._prepare_func(func)
+
+    def __call__(self, func):
+        self._prepare_func(func)
+        return self
+
+    def __get__(self, obj, cls):
+        if obj is None:
+            return self
+
+        now = time()
+        obj_dict = obj.__dict__
+        name = self.__name__
+        try:
+            value, last_updated = obj_dict[name]
+        except KeyError:
+            pass
+        else:
+            ttl_expired = self.ttl and self.ttl < now - last_updated
+            if not ttl_expired:
+                return value
+
+        value = self.func(obj)
+        obj_dict[name] = (value, now)
+        return value
+
+    def __delete__(self, obj):
+        obj.__dict__.pop(self.__name__, None)
+
+    def __set__(self, obj, value):
+        obj.__dict__[self.__name__] = (value, time())
+
+    def _prepare_func(self, func):
+        self.func = func
+        if func:
+            self.__doc__ = func.__doc__
+            self.__name__ = func.__name__
+            self.__module__ = func.__module__
+
+
+# Aliases to make cached_property_with_ttl easier to use
+cached_property_ttl = cached_property_with_ttl
+timed_cached_property = cached_property_with_ttl
+
+
+class threaded_cached_property_with_ttl(cached_property_with_ttl):
+    """
+    A cached_property version for use in environments where multiple threads
+    might concurrently try to access the property.
+    """
+
+    def __init__(self, ttl=None):
+        super(threaded_cached_property_with_ttl, self).__init__(ttl)
+        self.lock = threading.RLock()
+
+    def __get__(self, obj, cls):
+        with self.lock:
+            return super(threaded_cached_property_with_ttl, self).__get__(obj, cls)
+
+
+# Alias to make threaded_cached_property_with_ttl easier to use
+threaded_cached_property_ttl = threaded_cached_property_with_ttl
+timed_threaded_cached_property = threaded_cached_property_with_ttl