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/sets/setexpr.py

@@ -0,0 +1,97 @@
+from sympy.core import Expr
+from sympy.core.decorators import call_highest_priority, _sympifyit
+from .fancysets import ImageSet
+from .sets import set_add, set_sub, set_mul, set_div, set_pow, set_function
+
+
+class SetExpr(Expr):
+    """An expression that can take on values of a set.
+
+    Examples
+    ========
+
+    >>> from sympy import Interval, FiniteSet
+    >>> from sympy.sets.setexpr import SetExpr
+
+    >>> a = SetExpr(Interval(0, 5))
+    >>> b = SetExpr(FiniteSet(1, 10))
+    >>> (a + b).set
+    Union(Interval(1, 6), Interval(10, 15))
+    >>> (2*a + b).set
+    Interval(1, 20)
+    """
+    _op_priority = 11.0
+
+    def __new__(cls, setarg):
+        return Expr.__new__(cls, setarg)
+
+    set = property(lambda self: self.args[0])
+
+    def _latex(self, printer):
+        return r"SetExpr\left({}\right)".format(printer._print(self.set))
+
+    @_sympifyit('other', NotImplemented)
+    @call_highest_priority('__radd__')
+    def __add__(self, other):
+        return _setexpr_apply_operation(set_add, self, other)
+
+    @_sympifyit('other', NotImplemented)
+    @call_highest_priority('__add__')
+    def __radd__(self, other):
+        return _setexpr_apply_operation(set_add, other, self)
+
+    @_sympifyit('other', NotImplemented)
+    @call_highest_priority('__rmul__')
+    def __mul__(self, other):
+        return _setexpr_apply_operation(set_mul, self, other)
+
+    @_sympifyit('other', NotImplemented)
+    @call_highest_priority('__mul__')
+    def __rmul__(self, other):
+        return _setexpr_apply_operation(set_mul, other, self)
+
+    @_sympifyit('other', NotImplemented)
+    @call_highest_priority('__rsub__')
+    def __sub__(self, other):
+        return _setexpr_apply_operation(set_sub, self, other)
+
+    @_sympifyit('other', NotImplemented)
+    @call_highest_priority('__sub__')
+    def __rsub__(self, other):
+        return _setexpr_apply_operation(set_sub, other, self)
+
+    @_sympifyit('other', NotImplemented)
+    @call_highest_priority('__rpow__')
+    def __pow__(self, other):
+        return _setexpr_apply_operation(set_pow, self, other)
+
+    @_sympifyit('other', NotImplemented)
+    @call_highest_priority('__pow__')
+    def __rpow__(self, other):
+        return _setexpr_apply_operation(set_pow, other, self)
+
+    @_sympifyit('other', NotImplemented)
+    @call_highest_priority('__rtruediv__')
+    def __truediv__(self, other):
+        return _setexpr_apply_operation(set_div, self, other)
+
+    @_sympifyit('other', NotImplemented)
+    @call_highest_priority('__truediv__')
+    def __rtruediv__(self, other):
+        return _setexpr_apply_operation(set_div, other, self)
+
+    def _eval_func(self, func):
+        # TODO: this could be implemented straight into `imageset`:
+        res = set_function(func, self.set)
+        if res is None:
+            return SetExpr(ImageSet(func, self.set))
+        return SetExpr(res)
+
+
+def _setexpr_apply_operation(op, x, y):
+    if isinstance(x, SetExpr):
+        x = x.set
+    if isinstance(y, SetExpr):
+        y = y.set
+    out = op(x, y)
+    return SetExpr(out)