Added support for PEP 758, which allows Python 3.14 and newer to supp…

[erictraut]

…ort multiple exceptions in an except clause without surrounding parentheses. This addresses #10546.

[github-actions]

Diff from mypy_primer, showing the effect of this PR on open source code:

sympy (https://github.com/sympy/sympy)
+   ...:554:13 - error: Cannot access attribute "canon_bp" for class "Expr"
+     Attribute "canon_bp" is unknown (reportAttributeAccessIssue)
+   ...:554:13 - error: Cannot access attribute "canon_bp" for class "One"
+     Attribute "canon_bp" is unknown (reportAttributeAccessIssue)
+   ...:554:13 - error: Cannot access attribute "canon_bp" for class "Zero"
+     Attribute "canon_bp" is unknown (reportAttributeAccessIssue)
+   ...:554:13 - error: Cannot access attribute "canon_bp" for class "TensExpr"
+     Attribute "canon_bp" is unknown (reportAttributeAccessIssue)
+   ...:558:15 - error: Cannot access attribute "canon_bp" for class "Expr"
+     Attribute "canon_bp" is unknown (reportAttributeAccessIssue)
+   ...:558:15 - error: Cannot access attribute "canon_bp" for class "Zero"
+     Attribute "canon_bp" is unknown (reportAttributeAccessIssue)
+   ...:558:15 - error: Cannot access attribute "canon_bp" for class "One"
+     Attribute "canon_bp" is unknown (reportAttributeAccessIssue)
+   ...:558:15 - error: Cannot access attribute "canon_bp" for class "NegativeOne"
+     Attribute "canon_bp" is unknown (reportAttributeAccessIssue)
+   ...:558:15 - error: Cannot access attribute "canon_bp" for class "Integer"
+     Attribute "canon_bp" is unknown (reportAttributeAccessIssue)
+   ...:558:15 - error: Cannot access attribute "canon_bp" for class "NaN"
+     Attribute "canon_bp" is unknown (reportAttributeAccessIssue)
+   ...:558:15 - error: Cannot access attribute "canon_bp" for class "ComplexInfinity"
+     Attribute "canon_bp" is unknown (reportAttributeAccessIssue)
+   ...:558:15 - error: Cannot access attribute "canon_bp" for class "Rational"
+     Attribute "canon_bp" is unknown (reportAttributeAccessIssue)
+   ...:558:15 - error: Cannot access attribute "canon_bp" for class "Infinity"
+     Attribute "canon_bp" is unknown (reportAttributeAccessIssue)
+   ...:558:15 - error: Cannot access attribute "canon_bp" for class "NegativeInfinity"
+     Attribute "canon_bp" is unknown (reportAttributeAccessIssue)
+   ...:558:15 - error: Cannot access attribute "canon_bp" for class "Float"
+     Attribute "canon_bp" is unknown (reportAttributeAccessIssue)
+   ...:558:15 - error: Cannot access attribute "canon_bp" for class "Number"
+     Attribute "canon_bp" is unknown (reportAttributeAccessIssue)
+   ...:577:13 - error: Cannot access attribute "canon_bp" for class "Expr"
+     Attribute "canon_bp" is unknown (reportAttributeAccessIssue)
+   ...:577:13 - error: Cannot access attribute "canon_bp" for class "One"
+     Attribute "canon_bp" is unknown (reportAttributeAccessIssue)
+   ...:577:13 - error: Cannot access attribute "canon_bp" for class "NegativeOne"
+     Attribute "canon_bp" is unknown (reportAttributeAccessIssue)
+   ...:577:13 - error: Cannot access attribute "canon_bp" for class "Zero"
+     Attribute "canon_bp" is unknown (reportAttributeAccessIssue)
+   ...:577:13 - error: Cannot access attribute "canon_bp" for class "Integer"
+     Attribute "canon_bp" is unknown (reportAttributeAccessIssue)
+   ...:577:13 - error: Cannot access attribute "canon_bp" for class "NaN"
+     Attribute "canon_bp" is unknown (reportAttributeAccessIssue)
+   ...:577:13 - error: Cannot access attribute "canon_bp" for class "ComplexInfinity"
+     Attribute "canon_bp" is unknown (reportAttributeAccessIssue)
+   ...:577:13 - error: Cannot access attribute "canon_bp" for class "Rational"
+     Attribute "canon_bp" is unknown (reportAttributeAccessIssue)
+   ...:577:13 - error: Cannot access attribute "canon_bp" for class "Infinity"
+     Attribute "canon_bp" is unknown (reportAttributeAccessIssue)
+   ...:577:13 - error: Cannot access attribute "canon_bp" for class "NegativeInfinity"
+     Attribute "canon_bp" is unknown (reportAttributeAccessIssue)
+   ...:577:13 - error: Cannot access attribute "canon_bp" for class "Float"
+     Attribute "canon_bp" is unknown (reportAttributeAccessIssue)
+   ...:1602:36 - error: "__getitem__" method not defined on type "NegativeOne" (reportIndexIssue)
+   ...:1602:36 - error: "__getitem__" method not defined on type "One" (reportIndexIssue)
+   ...:1602:36 - error: "__getitem__" method not defined on type "TensExpr" (reportIndexIssue)
+   ...:1608:43 - error: "__getitem__" method not defined on type "NegativeOne" (reportIndexIssue)
+   ...:1608:43 - error: "__getitem__" method not defined on type "One" (reportIndexIssue)
+   ...:1608:43 - error: "__getitem__" method not defined on type "TensExpr" (reportIndexIssue)
+   ...:1694:44 - error: Cannot access attribute "data" for class "NegativeOne"
+     Attribute "data" is unknown (reportAttributeAccessIssue)
+   ...:1694:44 - error: Cannot access attribute "data" for class "One"
+     Attribute "data" is unknown (reportAttributeAccessIssue)
+   ...:1694:44 - error: Cannot access attribute "data" for class "TensExpr"
+     Attribute "data" is unknown (reportAttributeAccessIssue)
+   ...:288:16 - error: Type "Basic" is not assignable to declared type "Expr"
+     "Basic" is not assignable to "Expr" (reportAssignmentType)
-   ...:1802:43 - error: Cannot access attribute "simplify" for class "tuple[Unknown | Basic | Add | Dict, bool]"
+   ...:1802:43 - error: Cannot access attribute "simplify" for class "tuple[Unknown | Basic | Add | Expr | Mul | Dict, bool]"
-   ...:1828:48 - error: Cannot access attribute "simplify" for class "tuple[Unknown | Basic | Add | Dict, bool]"
+   ...:1828:48 - error: Cannot access attribute "simplify" for class "tuple[Unknown | Basic | Add | Expr | Mul | Dict, bool]"
+   ...:253:7 - error: Base classes for class "DyadicAdd" define method "as_content_primitive" in incompatible way
+     Return type mismatch: base method returns type "tuple[One, Self@Expr]", override returns type "tuple[One | NegativeOne | Zero | Integer | Expr | Unknown | Rational | NaN | ComplexInfinity, Expr | Unknown | Self@Add]"
+       "tuple[One | NegativeOne | Zero | Integer | Expr | Unknown | Rational | NaN | ComplexInfinity, Expr | Unknown | Self@Add]" is not assignable to "tuple[One, Self@Expr]"
+         Tuple entry 1 is incorrect type
+           Type "One | NegativeOne | Zero | Integer | Expr | Unknown | Rational | NaN | ComplexInfinity" is not assignable to type "One"
+             "Expr" is not assignable to "One" (reportIncompatibleMethodOverride)
+   ...:496:7 - error: Base classes for class "VectorAdd" define method "as_content_primitive" in incompatible way
+     Return type mismatch: base method returns type "tuple[One, Self@Expr]", override returns type "tuple[One | NegativeOne | Zero | Integer | Expr | Unknown | Rational | NaN | ComplexInfinity, Expr | Unknown | Self@Add]"
+       "tuple[One | NegativeOne | Zero | Integer | Expr | Unknown | Rational | NaN | ComplexInfinity, Expr | Unknown | Self@Add]" is not assignable to "tuple[One, Self@Expr]"
+         Tuple entry 1 is incorrect type
+           Type "One | NegativeOne | Zero | Integer | Expr | Unknown | Rational | NaN | ComplexInfinity" is not assignable to type "One"
+             "Expr" is not assignable to "One" (reportIncompatibleMethodOverride)
- 33352 errors, 74 warnings, 0 informations 
+ 33391 errors, 74 warnings, 0 informations