Can not subset embed fonts for a epub with "wide" Unicode char

[lishuode]

When I try to subset a embed a epub file, it failed. The problem is that the epub file contains a character which is U+22FF1, not in the Unicode 0 plane, but in the 2 plane. Thus the ord() function in Python2 can not handle it, which documented at https://docs.python.org/2/library/functions.html#ord .
I raised two idea here,
1. Use a special calibre_ord function(if we have) to instead the ord, this calibre_ord can handle the 1-17 plane of Unicode specially.
2. According to https://www.python.org/dev/peps/pep-0261/ , we can use python bits which complied with --enable-unicode=ucs4.

What's your idea?

Thanks,
Shuode Li

Here is the error details.

calibre, version 3.37.0
ERROR: Unhandled exception: <b>TypeError</b>:ord() expected a character, but string of length 2 found

calibre 3.37 [64bit] embedded-python: True is64bit: True
Windows-10-10.0.17763-SP0 Windows ('64bit', 'WindowsPE')
('Windows', '10', '10.0.17763')
Python 2.7.12+
Windows: ('10', '10.0.17763', 'SP0', u'Multiprocessor Free')
Interface language: None
Traceback (most recent call last):
  File "site-packages\calibre\gui2\tweak_book\boss.py", line 562, in polish
  File "site-packages\calibre\ebooks\oeb\polish\main.py", line 284, in tweak_polish
  File "site-packages\calibre\ebooks\oeb\polish\main.py", line 215, in polish_one
  File "site-packages\calibre\ebooks\oeb\polish\subset.py", line 69, in subset_all_fonts
  File "site-packages\calibre\utils\fonts\sfnt\subset.py", line 111, in subset
TypeError: ord() expected a character, but string of length 2 found

[Kovid Goyal (kovid)]

Fixed in branch master. The fix will be in the next release. calibre is usually released every alternate Friday.

 status fixreleased

[lishuode (lishuode)]

Awesome for the response time. Thanks so much Kovid