PEP 747: Clarify that TypeForm(T) is always a TypeForm[T] (#4736)

Author: davidfstr

peps/pep-0747.rst

@@ -289,11 +289,13 @@ Type checkers should validate that this argument is a valid type expression::
    x1 = TypeForm(str | None)
    reveal_type(v1)  # Revealed type is "TypeForm[str | None]"
 
-   x2 = TypeForm("list[int]")
+   x2 = TypeForm('list[int]')
    revealed_type(v2)  # Revealed type is "TypeForm[list[int]]"
 
    x3 = TypeForm('type(1)')  # Error: invalid type expression
 
+The static type of a ``TypeForm(T)`` is ``TypeForm[T]``.
+
 At runtime the ``TypeForm(...)`` callable simply returns the value passed to it.
 
 This explicit syntax serves two purposes. First, it documents the developer's