Simplify complex complex docs

Author: johnslavik

Doc/library/functions.rst

@@ -417,9 +417,9 @@ are always available.  They are listed here in alphabetical order.
    parts (the sign of the imaginary part is mandatory in this case).
    The string can optionally be surrounded by whitespaces and the round
    parentheses ``'('`` and ``')'``, which are ignored.
-   The string must not contain whitespace between ``'+'``, ``'-'``, ``'−'`` (U+2212), the
-   ``'j'`` or ``'J'`` suffix, and the decimal number.
-   For example, ``complex('1+2j')`` is fine, but ``complex('1 + 2j')`` raises
+   The string must not contain whitespace between ASCII plus sign ``'+'``, ASCII hyphen minus
+   ``'-'``, Unicode minus sign``'−'`` (U+2212), the ``'j'`` or ``'J'`` suffix, and the decimal
+   number. For example, ``complex('1+2j')`` is fine, but ``complex('1 + 2j')`` raises
    :exc:`ValueError`.
    More precisely, the input must conform to the :token:`~float:complexvalue`
    production rule in the following grammar, after parentheses and leading and