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/backoff/_common.py

@@ -0,0 +1,120 @@
+# coding:utf-8
+
+import functools
+import logging
+import sys
+import traceback
+import warnings
+
+
+# Use module-specific logger with a default null handler.
+_logger = logging.getLogger('backoff')
+_logger.addHandler(logging.NullHandler())  # pragma: no cover
+_logger.setLevel(logging.INFO)
+
+
+# Evaluate arg that can be either a fixed value or a callable.
+def _maybe_call(f, *args, **kwargs):
+    if callable(f):
+        try:
+            return f(*args, **kwargs)
+        except TypeError:
+            return f
+    else:
+        return f
+
+
+def _init_wait_gen(wait_gen, wait_gen_kwargs):
+    kwargs = {k: _maybe_call(v) for k, v in wait_gen_kwargs.items()}
+    initialized = wait_gen(**kwargs)
+    initialized.send(None)  # Initialize with an empty send
+    return initialized
+
+
+def _next_wait(wait, send_value, jitter, elapsed, max_time):
+    value = wait.send(send_value)
+    try:
+        if jitter is not None:
+            seconds = jitter(value)
+        else:
+            seconds = value
+    except TypeError:
+        warnings.warn(
+            "Nullary jitter function signature is deprecated. Use "
+            "unary signature accepting a wait value in seconds and "
+            "returning a jittered version of it.",
+            DeprecationWarning,
+            stacklevel=2,
+        )
+
+        seconds = value + jitter()
+
+    # don't sleep longer than remaining allotted max_time
+    if max_time is not None:
+        seconds = min(seconds, max_time - elapsed)
+
+    return seconds
+
+
+def _prepare_logger(logger):
+    if isinstance(logger, str):
+        logger = logging.getLogger(logger)
+    return logger
+
+
+# Configure handler list with user specified handler and optionally
+# with a default handler bound to the specified logger.
+def _config_handlers(
+    user_handlers, *, default_handler=None, logger=None, log_level=None
+):
+    handlers = []
+    if logger is not None:
+        assert log_level is not None, "Log level is not specified"
+        # bind the specified logger to the default log handler
+        log_handler = functools.partial(
+            default_handler, logger=logger, log_level=log_level
+        )
+        handlers.append(log_handler)
+
+    if user_handlers is None:
+        return handlers
+
+    # user specified handlers can either be an iterable of handlers
+    # or a single handler. either way append them to the list.
+    if hasattr(user_handlers, '__iter__'):
+        # add all handlers in the iterable
+        handlers += list(user_handlers)
+    else:
+        # append a single handler
+        handlers.append(user_handlers)
+
+    return handlers
+
+
+# Default backoff handler
+def _log_backoff(details, logger, log_level):
+    msg = "Backing off %s(...) for %.1fs (%s)"
+    log_args = [details['target'].__name__, details['wait']]
+
+    exc_typ, exc, _ = sys.exc_info()
+    if exc is not None:
+        exc_fmt = traceback.format_exception_only(exc_typ, exc)[-1]
+        log_args.append(exc_fmt.rstrip("\n"))
+    else:
+        log_args.append(details['value'])
+    logger.log(log_level, msg, *log_args)
+
+
+# Default giveup handler
+def _log_giveup(details, logger, log_level):
+    msg = "Giving up %s(...) after %d tries (%s)"
+    log_args = [details['target'].__name__, details['tries']]
+
+    exc_typ, exc, _ = sys.exc_info()
+    if exc is not None:
+        exc_fmt = traceback.format_exception_only(exc_typ, exc)[-1]
+        log_args.append(exc_fmt.rstrip("\n"))
+    else:
+        log_args.append(details['value'])
+
+    logger.log(log_level, msg, *log_args)