gh-156233: Fix the prior author's 'overly_generic' example's Python SyntaxError, and type annotation errors

[willy-b]

Thanks so much Python team for everything you do. In discussion with @StanFromIreland at #156475 (comment) and @encukou at #156233 (comment) , I have opened this PR to fix the Compound Statement documentation page's 'overly_generic' example's Python SyntaxError, and type annotation errors (ParamSpec default given as a tuple (instead of List), TypeVarTuple default specified as a plain packed tuple instead of unpacked) by prior author.

Re: the 'Compound Statement's overly_generic example on https://docs.python.org/3.16/reference/compound_stmts.html (archived as is at https://web.archive.org/web/20260913010111/https://docs.python.org/3.16/reference/compound_stmts.html ) (and docs for earlier Python versions, e.g. 3.13, 3.14, 3.15), this commit makes minimal changes specific to this example only to:

• Fix Python SyntaxError: non-default type parameter 'TypeVarWithBound' follows default type parameter for the overly_generic by moving the TypeVarwithDefault down in the list after the non-default type parameters (from

  cpython/Doc/reference/compound_stmts.rst

  Line 1852 in fe3a26f

  TypeVarWithDefault = int,

  )
• Fix MyPy error: The default argument to ParamSpec must be a list expression, ellipsis, or a ParamSpec [misc] by substituting **SimpleParamSpec=[str, bytearray] instead of the invalid **SimpleParamSpec=[str, bytearray] (fixing

  cpython/Doc/reference/compound_stmts.rst

  Line 1856 in fe3a26f

  **SimpleParamSpec = (str, bytearray),

  ) to follow guidance at e.g. https://typing.python.org/en/latest/spec/generics.html#paramspec-defaults (archived as is at https://web.archive.org/web/20260913004550/https://typing.python.org/en/latest/spec/generics.html#paramspec-defaults )
• Fix MyPy error: The default argument to TypeVarTuple must be an Unpacked tuple [misc] by replacing *SimpleTypeVarTuple = (int, float), with *SimpleTypeVarTuple = *tuple[int, float], (fixing

  cpython/Doc/reference/compound_stmts.rst

  Line 1855 in fe3a26f

  *SimpleTypeVarTuple = (int, float),

  ) to follow guidance at e.g. https://typing.python.org/en/latest/spec/generics.html#typevartuple-defaults (archived as is at https://web.archive.org/web/20260913004550/https://typing.python.org/en/latest/spec/generics.html#typevartuple-defaults )
• Fix MyPy error: TypeVarTuple 'SimpleTypeVarTuple' is only valid with an unpack [valid-type] by replacing *e: SimpleTypeVarTuple, with *e: *SimpleTypeVarTuple, to follow guidance at e.g. https://typing.python.org/en/latest/spec/generics.html#args-as-a-type-variable-tuple (archived as is at https://web.archive.org/web/20260913004550/https://typing.python.org/en/latest/spec/generics.html#args-as-a-type-variable-tuple )

See motivating discussion at #156233 (comment) and #156233 (comment) .

Should be backported from 3.16 through 3.13. Checked this example also on the lower version of Python 3.13.2 with MyPy 2.3.1 , PyreFly 1.3.0 , Pyright 1.1.414 .

(Re further backports: Note the version of the page on 3.12 did not have default type parameters but probably still needs a SEPARATE fix for

cpython/Doc/reference/compound_stmts.rst

Line 1718 in c016c25

*d: SimpleTypeVarTuple,

in that branch to unpack the tuple (in that branch SimpleTypeVarTuple doesn't have a default but is still used unpacked, so only one line needs to change)).

• Issue: A few typos, grammar mistakes, and code snippet errors in the docs #156233

[willy-b]

Note that MyPy has its own bug that it cannot handle typed varargs after some other typed arguments like Callables preceding it, e.g. as I reported earlier in python/mypy#21907 , which one trying related examples may encounter (that exists prior to updating this example to use correct type annotations per the instructions at https://typing.python.org/en/latest/spec/generics.html , though I may subsequently try to fix that bug now that this example indirectly brought my attention to it ).

[read-the-docs-community]

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