python: unicode in Windows terminal, encoding used?

Question

I am using the Python interpreter in Windows 7 terminal.
I am trying to wrap my head around unicode and encodings.

I type:

>>> s='?'
>>> s
'x89'
>>> u=u'?'
>>> u
u'xeb'

Question 1: Why is the encoding used in the string s different from the one used in the unicode string u?

I continue, and type:

>>> us=unicode(s)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
UnicodeDecodeError: 'ascii' codec can't decode byte 0x89 in position 0: ordinal
not in range(128)
>>> us=unicode(s, 'latin-1')
>>> us
u'x89'

Question2: I tried using the latin-1 encoding on good luck to turn the string into an unicode string (actually, I tried a bunch of other ones first, including utf-8). How can I find out which encoding the terminal has used to encode my string?

Question 3: how can I make the terminal print ? as ? instead of 'x89' or u'xeb'? Hmm, stupid me. print(s) does the job.

I already looked at this related SO question, but no clues from there: Set Python terminal encoding on Windows

Answer 1

Unicode is not an encoding. You encode into byte strings and decode into Unicode:

>>> 'x89'.decode('cp437')
u'xeb'
>>> u'xeb'.encode('cp437')
'x89'
>>> u'xeb'.encode('utf8')
'xc3xab'

The windows terminal uses legacy code pages for DOS. For US Windows it is:

>>> import sys
>>> sys.stdout.encoding
'cp437'

Windows applications use windows code pages. Python's IDLE will show the windows encoding:

>>> import sys
>>> sys.stdout.encoding
'cp1252'

Your results may vary.