def is_valid_xml_char_ordinal(i):
    """
    Defines whether char is valid to use in xml document

    XML standard defines a valid char as::

    Char ::= #x9 | #xA | #xD | [#x20-#xD7FF] | [#xE000-#xFFFD] | [#x10000-#x10FFFF]
    """
    return (
        # conditions ordered by presumed frequency
        0x20 <= i <= 0xD7FF
        or i in (0x9, 0xA, 0xD)
        or 0xE000 <= i <= 0xFFFD
        or 0x10000 <= i <= 0x10FFFF
    )