The explanation of "Annotating callable objects" section should be made better

[hyperkai]

Documentation

*Notes:

• Python 3.14.3
• Related: _CallableGenericAlias class and typing.Callable docstring should be corrected #145602

In the explanation of Annotating callable objects section, some words or sentence aren't clear, distinct, specific, concise and less common, and the word argument is misused, etc. So they should be corrected:

<Some examples>

The 1st one:

*Notes:

• "has" is better than "takes" because "takes" sounds taking an argument but not parameter:

... a function that takes a single parameter of type int and returns a str.

... a function that has a single parameter of type int and returns a str.

The 2nd one:

*Notes:

• Naming and calling [] "type specification" is more understandable than "subscription syntax".
• "must" is enough for emphasis so "always" and "exactly" aren't needed, emphasizing too much.
• "two objects" are better than "two values" because "two values" sounds actual values like v = "Hello"'s "Hello" so it's confusing while talking about types.
• "parameter type list" is better than "argument list" because "parameter" is correct and "type list" is more specific and understandable.

The subscription syntax must always be used with exactly two values: the
argument list and the return type.

The type specification [] must have two objects, a parameter type list and return type.

etc.

Linked PRs

• gh-145577: Correct "Annotating callable objects" explanation #145576
• gh-145602: Correct _CallableGenericAlias class and typing.Callable docstring #145598