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/sympy/conftest.py

@@ -0,0 +1,96 @@
+import sys
+
+sys._running_pytest = True  # type: ignore
+from sympy.external.importtools import version_tuple
+
+import pytest
+from sympy.core.cache import clear_cache, USE_CACHE
+from sympy.external.gmpy import GROUND_TYPES
+from sympy.utilities.misc import ARCH
+import re
+
+try:
+    import hypothesis
+
+    hypothesis.settings.register_profile("sympy_hypothesis_profile", deadline=None)
+    hypothesis.settings.load_profile("sympy_hypothesis_profile")
+except ImportError:
+    raise ImportError(
+        "hypothesis is a required dependency to run the SymPy test suite. "
+        "Install it with 'pip install hypothesis' or 'conda install -c conda-forge hypothesis'"
+    )
+
+
+sp = re.compile(r"([0-9]+)/([1-9][0-9]*)")
+
+
+def process_split(config, items):
+    split = config.getoption("--split")
+    if not split:
+        return
+    m = sp.match(split)
+    if not m:
+        raise ValueError(
+            "split must be a string of the form a/b " "where a and b are ints."
+        )
+    i, t = map(int, m.groups())
+    start, end = (i - 1) * len(items) // t, i * len(items) // t
+
+    if i < t:
+        # remove elements from end of list first
+        del items[end:]
+    del items[:start]
+
+
+def pytest_report_header(config):
+    s = "architecture: %s\n" % ARCH
+    s += "cache:        %s\n" % USE_CACHE
+    version = ""
+    if GROUND_TYPES == "gmpy":
+        import gmpy2
+
+        version = gmpy2.version()
+    elif GROUND_TYPES == "flint":
+        try:
+            from flint import __version__
+        except ImportError:
+            version = "unknown"
+        else:
+            version = f'(python-flint=={__version__})'
+    s += "ground types: %s %s\n" % (GROUND_TYPES, version)
+    return s
+
+
+def pytest_terminal_summary(terminalreporter):
+    if terminalreporter.stats.get("error", None) or terminalreporter.stats.get(
+        "failed", None
+    ):
+        terminalreporter.write_sep(" ", "DO *NOT* COMMIT!", red=True, bold=True)
+
+
+def pytest_addoption(parser):
+    parser.addoption("--split", action="store", default="", help="split tests")
+
+
+def pytest_collection_modifyitems(config, items):
+    """pytest hook."""
+    # handle splits
+    process_split(config, items)
+
+
+@pytest.fixture(autouse=True, scope="module")
+def file_clear_cache():
+    clear_cache()
+
+
+@pytest.fixture(autouse=True, scope="module")
+def check_disabled(request):
+    if getattr(request.module, "disabled", False):
+        pytest.skip("test requirements not met.")
+    elif getattr(request.module, "ipython", False):
+        # need to check version and options for ipython tests
+        if (
+            version_tuple(pytest.__version__) < version_tuple("2.6.3")
+            and pytest.config.getvalue("-s") != "no"
+        ):
+            pytest.skip("run py.test with -s or upgrade to newer version.")