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/graphviz/piping.py

@@ -0,0 +1,161 @@
+"""Pipe DOT code objects through Graphviz ``dot``."""
+
+import codecs
+import logging
+import typing
+
+from . import _tools
+from . import backend
+from . import exceptions
+from . import base
+from . import encoding
+
+__all__ = ['Pipe']
+
+
+log = logging.getLogger(__name__)
+
+
+class Pipe(encoding.Encoding, base.Base, backend.Pipe):
+    """Pipe source lines through the Graphviz layout command."""
+
+    @typing.overload
+    def pipe(self,
+             format: typing.Optional[str] = ...,
+             renderer: typing.Optional[str] = ...,
+             formatter: typing.Optional[str] = ...,
+             neato_no_op: typing.Union[bool, int, None] = ...,
+             quiet: bool = ..., *,
+             engine: typing.Optional[str] = ...,
+             encoding: None = ...) -> bytes:
+        """Return bytes with default ``encoding=None``."""
+
+    @typing.overload
+    def pipe(self,
+             format: typing.Optional[str] = ...,
+             renderer: typing.Optional[str] = ...,
+             formatter: typing.Optional[str] = ...,
+             neato_no_op: typing.Union[bool, int, None] = ...,
+             quiet: bool = ..., *,
+             engine: typing.Optional[str] = ...,
+             encoding: str) -> str:
+        """Return string when given encoding."""
+
+    @typing.overload
+    def pipe(self,
+             format: typing.Optional[str] = ...,
+             renderer: typing.Optional[str] = ...,
+             formatter: typing.Optional[str] = ...,
+             neato_no_op: typing.Union[bool, int, None] = ...,
+             quiet: bool = ..., *,
+             engine: typing.Optional[str] = ...,
+             encoding: typing.Optional[str]) -> typing.Union[bytes, str]:
+        """Return bytes or string depending on encoding argument."""
+
+    def pipe(self,
+             format: typing.Optional[str] = None,
+             renderer: typing.Optional[str] = None,
+             formatter: typing.Optional[str] = None,
+             neato_no_op: typing.Union[bool, int, None] = None,
+             quiet: bool = False, *,
+             engine: typing.Optional[str] = None,
+             encoding: typing.Optional[str] = None) -> typing.Union[bytes, str]:
+        """Return the source piped through the Graphviz layout command.
+
+        Args:
+            format: The output format used for rendering
+                (``'pdf'``, ``'png'``, etc.).
+            renderer: The output renderer used for rendering
+                (``'cairo'``, ``'gd'``, ...).
+            formatter: The output formatter used for rendering
+                (``'cairo'``, ``'gd'``, ...).
+            neato_no_op: Neato layout engine no-op flag.
+            quiet (bool): Suppress ``stderr`` output
+                from the layout subprocess.
+            engine: Layout engine for rendering
+                (``'dot'``, ``'neato'``, ...).
+            encoding: Encoding for decoding the stdout.
+
+        Returns:
+            Bytes or if encoding is given decoded string
+                (stdout of the layout command).
+
+        Raises:
+            ValueError: If ``engine``, ``format``, ``renderer``, or ``formatter``
+                are unknown.
+            graphviz.RequiredArgumentError: If ``formatter`` is given
+                but ``renderer`` is None.
+            graphviz.ExecutableNotFound: If the Graphviz ``dot`` executable
+                is not found.
+            graphviz.CalledProcessError: If the returncode (exit status)
+                of the rendering ``dot`` subprocess is non-zero.
+
+        Example:
+            >>> doctest_mark_exe()
+            >>> import graphviz
+            >>> source = 'graph { spam }'
+            >>> graphviz.Source(source, format='svg').pipe()[:14]
+            b'<?xml version='
+            >>> graphviz.Source(source, format='svg').pipe(encoding='ascii')[:14]
+            '<?xml version='
+            >>> graphviz.Source(source, format='svg').pipe(encoding='utf-8')[:14]
+            '<?xml version='
+        """
+        return self._pipe_legacy(format,
+                                 renderer=renderer,
+                                 formatter=formatter,
+                                 neato_no_op=neato_no_op,
+                                 quiet=quiet,
+                                 engine=engine,
+                                 encoding=encoding)
+
+    @_tools.deprecate_positional_args(supported_number=1, ignore_arg='self')
+    def _pipe_legacy(self,
+                     format: typing.Optional[str] = None,
+                     renderer: typing.Optional[str] = None,
+                     formatter: typing.Optional[str] = None,
+                     neato_no_op: typing.Union[bool, int, None] = None,
+                     quiet: bool = False, *,
+                     engine: typing.Optional[str] = None,
+                     encoding: typing.Optional[str] = None) -> typing.Union[bytes, str]:
+        return self._pipe_future(format,
+                                 renderer=renderer,
+                                 formatter=formatter,
+                                 neato_no_op=neato_no_op,
+                                 quiet=quiet,
+                                 engine=engine,
+                                 encoding=encoding)
+
+    def _pipe_future(self, format: typing.Optional[str] = None, *,
+                     renderer: typing.Optional[str] = None,
+                     formatter: typing.Optional[str] = None,
+                     neato_no_op: typing.Union[bool, int, None] = None,
+                     quiet: bool = False,
+                     engine: typing.Optional[str] = None,
+                     encoding: typing.Optional[str] = None) -> typing.Union[bytes, str]:
+        args, kwargs = self._get_pipe_parameters(engine=engine,
+                                                 format=format,
+                                                 renderer=renderer,
+                                                 formatter=formatter,
+                                                 neato_no_op=neato_no_op,
+                                                 quiet=quiet,
+                                                 verify=True)
+
+        args.append(iter(self))
+
+        if encoding is not None:
+            if codecs.lookup(encoding) is codecs.lookup(self.encoding):
+                # common case: both stdin and stdout need the same encoding
+                return self._pipe_lines_string(*args, encoding=encoding, **kwargs)
+            try:
+                raw = self._pipe_lines(*args, input_encoding=self.encoding, **kwargs)
+            except exceptions.CalledProcessError as e:
+                *args, output, stderr = e.args
+                if output is not None:
+                    output = output.decode(self.encoding)
+                if stderr is not None:
+                    stderr = stderr.decode(self.encoding)
+                raise e.__class__(*args, output=output, stderr=stderr)
+            else:
+                return raw.decode(encoding)
+        return self._pipe_lines(*args, input_encoding=self.encoding, **kwargs)