As per title PyUnicode functions, such as PyUnicode_FromWideChar, are not exported on Ubuntu and possibly other Linux systems.  This is a show stopper for embedded Python.

To confirm:

>>> import ctypes
>>> hasattr(ctypes.pythonapi, "PyUnicode_FromWideChar")

It should return True, but it returns False.  

I have tested with the default Ubuntu python 2.7.15 and with compiled python 2.7.16.

Note that the problem does not exist in python3 and also python 2.7 and 3.x in Windows.  So it is only python 2.7 in Ubuntu.

Given that 2.7 is reaching end-of-life in a single-digit number of months, I doubt anything will be changed here.  I'll leave it up to Benjamin to make that determination, though.

> hasattr(ctypes.pythonapi, "PyUnicode_FromWideChar")

Python 2 has a surprising ABI. The function names depending on the Unicode implementation:

PyUnicodeUCS2_FromWideChar on Windows, PyUnicodeUCS4_FromWideChar on other platforms.

Enjoy the ugly https://github.com/python/cpython/blob/2.7/Include/unicodeobject.h

And say hello to the new compact Unicode strings, PEP 393, implemented in Python 3.3, which unified that!
https://www.python.org/dev/peps/pep-0393/

To Victor:

Neither of PyUnicodeUCS2_FromWideChar or PyUnicodeUCS4_FromWideChar is exported.

>>> import ctypes
>>> hasattr(ctypes.pythonapi, "PyUnicode_FromWideChar")
>>> hasattr(ctypes.pythonapi, "PyUnicodeUSC4_FromWideChar")
>>> hasattr(ctypes.pythonapi, "PyUnicodeUSC2_FromWideChar")

all return false on Ubuntu.

ctypes.pythonapi is kind of magic. I'm not sure if hasattr() is supposed to work on it. But that works for me:

$ python2
Python 2.7.16 (default, Apr 30 2019, 15:54:43) 
>>> import ctypes
>>> ctypes.pythonapi.PyUnicodeUCS4_FromWideChar
<_FuncPtr object at 0x7f1b9c155ef0>

I meant PyUnicodeUCS4_FromWideChar PyUnicodeUCS2_FromWideChar.

Is this on Ubuntu?

> Is this on Ubuntu?

No, only Fedora. If the issue is specific to Ubuntu, report it to the Ubuntu bug tracker.

>>> sys.version
'2.7.16 (default, Oct  7 2019, 17:16:30) \n[GCC 7.4.0]'
>>> ctypes.pythonapi.PyUnicodeUCS4_FromWideChar
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/usr/local/lib/python2.7/ctypes/__init__.py", line 379, in __getattr__
    func = self.__getitem__(name)
  File "/usr/local/lib/python2.7/ctypes/__init__.py", line 384, in __getitem__
    func = self._FuncPtr((name_or_ordinal, self))
AttributeError: python2.7: undefined symbol: PyUnicodeUCS4_FromWideChar
>>>