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Date: Sun, 10 May 2015 17:53:08 +0200
Subject: Why does unicode-escape decode escape symbols that are already escaped?
From: "Somelauw ." <somelauw@gmail.com>
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In Python 3, decoding "=E2=82=AC" with unicode-escape returns '=C3=A2\x82=
=C2=AC' which in my
opinion doesn't make sense.
The =E2=82=AC already is decoded; if it were encoded it would look like thi=
s:
'\u20ac'.
So why is it doing this?

In Python 2 the behaviour is similar, but slightly different.

$ python3 -S
Python 3.3.3 (default, Nov 27 2013, 17:12:35)
[GCC 4.8.2] on linux
>>> import codecs
>>> codecs.decode('=E2=82=AC', 'unicode-escape')
'=C3=A2\x82=C2=AC'
>>> codecs.encode('=E2=82=AC', 'unicode-escape')
b'\\u20ac'
>>>

$ python2 -S
Python 2.7.5+ (default, Sep 17 2013, 15:31:50)
[GCC 4.8.1] on linux2
>>> import codecs
>>> codecs.decode('=E2=82=AC', 'unicode-escape')
u'\xe2\x82\xac'
>>> codecs.encode('=E2=82=AC', 'unicode-escape')
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
UnicodeDecodeError: 'ascii' codec can't decode byte 0xe2 in position 0:
ordinal not in range(128)
>>>

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<div dir=3D"ltr"><div>In Python 3, decoding &quot;=E2=82=AC&quot; with unic=
ode-escape returns &#39;=C3=A2\x82=C2=AC&#39; which in my opinion doesn&#39=
;t make sense.<br></div><div><div>The =E2=82=AC already is decoded; if it w=
ere encoded it would look like this: &#39;\u20ac&#39;.</div></div><div>So w=
hy is it doing this?</div><div><br></div><div>In Python 2 the behaviour is =
similar, but slightly different.</div><div><br></div><div><div>$ python3 -S=
</div><div>Python 3.3.3 (default, Nov 27 2013, 17:12:35)=C2=A0</div><div>[G=
CC 4.8.2] on linux</div><div>&gt;&gt;&gt; import codecs<br></div></div><div=
><div>&gt;&gt;&gt; codecs.decode(&#39;=E2=82=AC&#39;, &#39;unicode-escape&#=
39;)<br></div><div>&#39;=C3=A2\x82=C2=AC&#39;</div><div>&gt;&gt;&gt; codecs=
.encode(&#39;=E2=82=AC&#39;, &#39;unicode-escape&#39;)</div><div>b&#39;\\u2=
0ac&#39;</div><div>&gt;&gt;&gt;</div></div><div><br></div><div><div>$ pytho=
n2 -S</div><div>Python 2.7.5+ (default, Sep 17 2013, 15:31:50)=C2=A0</div><=
div>[GCC 4.8.1] on linux2</div><div>&gt;&gt;&gt; import codecs<br></div><di=
v>&gt;&gt;&gt; codecs.decode(&#39;=E2=82=AC&#39;, &#39;unicode-escape&#39;)=
</div><div>u&#39;\xe2\x82\xac&#39;</div></div><div><div>&gt;&gt;&gt; codecs=
.encode(&#39;=E2=82=AC&#39;, &#39;unicode-escape&#39;)</div><div>Traceback =
(most recent call last):</div><div>=C2=A0 File &quot;&lt;stdin&gt;&quot;, l=
ine 1, in &lt;module&gt;</div><div>UnicodeDecodeError: &#39;ascii&#39; code=
c can&#39;t decode byte 0xe2 in position 0: ordinal not in range(128)</div>=
<div>&gt;&gt;&gt;</div></div><div><br></div><div><br></div></div>

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