unicode to python object conversion - python

Given a unicode object:
u'[obj1,obj2,ob3]'
How do you convert it to a normal list of objects?

import ast
s = u'[obj1,obj2,ob3]'
n = ast.literal_eval(s)
n
[obj1, obj2, ob3]

Did you mean this? Converting a unicode string to a list of strings.
BTW, you need to know the encoding when dealing with unicode. Here I have used utf-8
>>> s = u'[obj1,obj2,ob3]'
>>> n = [e.encode('utf-8') for e in s.strip('[]').split(',')]
>>> n
['obj1', 'obj2', 'ob3']

What you posted is a unicode string.
To encode it e.g. as UTF-8 use yourutf8str = yourunicodestr.encode('utf-8')

When unicode data doesn't show unicode u...
On exporting data from an excel table using openpyxl, my unicode was invisible. Use print repr(s) to see it
>>>print(data)
>>>print(type(data))
["Independent", "Primary/Secondary Combined", "Coed", "Anglican", "Boarding"]
<type 'unicode>
>>>print repr(data)
u'["Independent", "Primary/Secondary Combined", "Coed", "Anglican", "Boarding"]'
The fix:
>>>import ast
>>>data = ast.literal_eval(entry)
>>>print(data)
>>>print(type(data))
["Independent", "Primary/Secondary Combined", "Coed", "Anglican", "Boarding"]
<type 'list'>

Related

How to decode a string representation of a bytes object?

I have a string which includes encoded bytes inside it:
str1 = "b'Output file \xeb\xac\xb8\xed\x95\xad\xeb\xb6\x84\xec\x84\x9d.xlsx Created'"
I want to decode it, but I can't since it has become a string. Therefore I want to ask whether there is any way I can convert it into
str2 = b'Output file \xeb\xac\xb8\xed\x95\xad\xeb\xb6\x84\xec\x84\x9d.xlsx Created'
Here str2 is a bytes object which I can decode easily using
str2.decode('utf-8')
to get the final result:
'Output file 문항분석.xlsx Created'
You could use ast.literal_eval:
>>> print(str1)
b'Output file \xeb\xac\xb8\xed\x95\xad\xeb\xb6\x84\xec\x84\x9d.xlsx Created'
>>> type(str1)
<class 'str'>
>>> from ast import literal_eval
>>> literal_eval(str1).decode('utf-8')
'Output file 문항분석.xlsx Created'
Based on the SyntaxError mentioned in your comments, you may be having a testing issue when attempting to print due to the fact that stdout is set to ascii in your console (and you may also find that your console does not support some of the characters you may be trying to print). You can try something like the following to set sys.stdout to utf-8 and see what your console will print (just using string slice and encode below to get bytes rather than the ast.literal_eval approach that has already been suggested):
import codecs
import sys
sys.stdout = codecs.getwriter('utf-8')(sys.stdout.buffer)
s = "b'Output file \xeb\xac\xb8\xed\x95\xad\xeb\xb6\x84\xec\x84\x9d.xlsx Created'"
b = s[2:-1].encode().decode('utf-8')
A simple way is to assume that all the characters of the initial strings are in the [0,256) range and map to the same Unicode value, which means that it is a Latin1 encoded string.
The conversion is then trivial:
str1[2:-1].encode('Latin1').decode('utf8')
Finally I have found an answer where i use a function to cast a string to bytes without encoding.Given string
str1 = "b'Output file \xeb\xac\xb8\xed\x95\xad\xeb\xb6\x84\xec\x84\x9d.xlsx Created'"
now i take only actual encoded text inside of it
str1[2:-1]
and pass this to the function which convert the string to bytes without encoding its values
import struct
def rawbytes(s):
"""Convert a string to raw bytes without encoding"""
outlist = []
for cp in s:
num = ord(cp)
if num < 255:
outlist.append(struct.pack('B', num))
elif num < 65535:
outlist.append(struct.pack('>H', num))
else:
b = (num & 0xFF0000) >> 16
H = num & 0xFFFF
outlist.append(struct.pack('>bH', b, H))
return b''.join(outlist)
So, calling the function would convert it to bytes which then is decoded
rawbytes(str1[2:-1]).decode('utf-8')
will give the correct output
'Output file 문항분석.xlsx Created'

Python encoding unicode utf-8

I'm using selenium to insert text input with german umlauts in a web formular. The declared coding for the python script is utf-8. The page uses utf-8 encoding. When i definine a string like that everything works fine:
q = u"Hällö" #type(q) returns unicode
...
textbox.send_keys(q)
But when i try to read from a config file using ConfigParser (or another kind of file) i get malformed output in the webformular (Hällö). This is the code i use for that:
the_encoding = chardet.detect(q)['encoding'] #prints utf-8
q = parser.get('info', 'query') # type(q) returns str
q = q.decode('unicode-escape') # type(q) returns unicode
textbox.send_keys(q)
Whats the difference between the both q's given to the send_keys function?
This is probably bad encoding. Try printing q before the last statement, and see if it's equal. This line q = parser.get('info', 'query') # type(q) returns str should return the string 'H\xc3\xa4ll\xc3\xb6'. If it's different, then you are using the wrong coding.
>>> q = u"Hällö" # unicode obj
>>> q
u'H\xe4ll\xf6'
>>> print q
Hällö
>>> q.encode('utf-8')
'H\xc3\xa4ll\xc3\xb6'
>>> a = q.encode('utf-8') # str obj
>>> a
'H\xc3\xa4ll\xc3\xb6' # <-- this should be the value of the str
>>> a.decode('utf-8') # <-- unicode obj
u'H\xe4ll\xf6'
>>> print a.decode('utf-8')
Hällö
>>>
from ConfigParser import SafeConfigParser
import codecs
parser = SafeConfigParser()
with codecs.open('cfg.ini', 'r', encoding='utf-8-sig') as f:
parser.readfp(f)
greet = parser.get('main', 'greet')
print 'greet:', greet.encode('utf-8-sig')
greet: Hällö
cfg.ini file
[main]
greet=Hällö

Turn a bytes-like string into actual bytes in Python

Is there a build-in function in python 3 to let me get b from a?
a = '\\xe9\\x82\\xa3'
b = b'\xe9\x82\xa3'
You can use unicode-escape encoding:
>>> a = '\\xe9\\x82\\xa3'
>>> a.encode().decode('unicode-escape').encode('latin1')
b'\xe9\x82\xa3'
>>> import codecs
>>> codecs.decode(a, 'unicode-escape').encode('latin1')
b'\xe9\x82\xa3'

Python: unescape "\xXX"

I have a string with escaped data like
escaped_data = '\\x50\\x51'
print escaped_data # gives '\x50\x51'
What Python function would unescape it so I would get
raw_data = unescape( escaped_data)
print raw_data # would print "PQ"
You can decode with string-escape.
>>> escaped_data = '\\x50\\x51'
>>> escaped_data.decode('string-escape')
'PQ'
In Python 3.0 there's no string-escape, but you can use unicode_escape.
From a bytes object:
>>> escaped_data = b'\\x50\\x51'
>>> escaped_data.decode("unicode_escape")
'PQ'
From a Unicode str object:
>>> import codecs
>>> escaped_data = '\\x50\\x51'
>>> codecs.decode(escaped_data, "unicode_escape")
'PQ'
You could use the 'unicode_escape' codec:
>>> '\\x50\\x51'.decode('unicode_escape')
u'PQ'
Alternatively, 'string-escape' will give you a classic Python 2 string (bytes in Python 3):
>>> '\\x50\\x51'.decode('string_escape')
'PQ'
escaped_data.decode('unicode-escape') helps?
Try:
eval('"' + raw_data + '"')
It should work.

Python to show special characters

I know there are tons of threads regarding this issue but I have not managed to find one which solves my problem.
I am trying to print a string but when printed it doesn't show special characters (e.g. æ, ø, å, ö and ü). When I print the string using repr() this is what I get:
u'Von D\xc3\xbc' and u'\xc3\x96berg'
Does anyone know how I can convert this to Von Dü and Öberg? It's important to me that these characters are not ignored, e.g. myStr.encode("ascii", "ignore").
EDIT
This is the code I use. I use BeautifulSoup to scrape a website. The contents of a cell (<td>) in a table (<table>), is put into the variable name. This is the variable which contains special characters that I cannot print.
web = urllib2.urlopen(url);
soup = BeautifulSoup(web)
tables = soup.find_all("table")
scene_tables = [2, 3, 6, 7, 10]
scene_index = 0
# Iterate over the <table>s we want to work with
for scene_table in scene_tables:
i = 0
# Iterate over < td> to find time and name
for td in tables[scene_table].find_all("td"):
if i % 2 == 0: # td contains the time
time = remove_whitespace(td.get_text())
else: # td contains the name
name = remove_whitespace(td.get_text()) # This is the variable containing "nonsense"
print "%s: %s" % (time, name,)
i += 1
scene_index += 1
Prevention is better than cure. What you need is to find out how that rubbish is being created. Please edit your question to show the code that creates it, and then we can help you fix it. It looks like somebody has done:
your_unicode_string = original_utf8_encoded_bytestring.decode('latin1')
The cure is to reverse the process, simply, and then decode.
correct_unicode_string = your_unicode_string.encode('latin1').decode('utf8')
Update Based on the code that you supplied, the probable cause is that the website declares that it is encoded in ISO-8859-1 (aka latin1) but in reality it is encoded in UTF-8. Please update your question to show us the url.
If you can't show it, read the BS docs; it looks like you'll need to use:
BeautifulSoup(web, from_encoding='utf8')
Unicode support in many languages is confusing, so your error here is understandable. Those strings are UTF-8 bytes, which would work properly if you drop the u at the front:
>>> err = u'\xc3\x96berg'
>>> print err
Ã?berg
>>> x = '\xc3\x96berg'
>>> print x
Öberg
>>> u = x.decode('utf-8')
>>> u
u'\xd6berg'
>>> print u
Öberg
For lots more information:
http://www.joelonsoftware.com/articles/Unicode.html
http://docs.python.org/howto/unicode.html
You should really really read those links and understand what is going on before proceeding. If, however, you absolutely need to have something that works today, you can use this horrible hack that I am embarrassed to post publicly:
def convert_fake_unicode_to_real_unicode(string):
return ''.join(map(chr, map(ord, string))).decode('utf-8')
The contents of the strings are not unicode, they are UTF-8 encoded.
>>> print u'Von D\xc3\xbc'
Von Dü
>>> print 'Von D\xc3\xbc'
Von Dü
>>> print unicode('Von D\xc3\xbc', 'utf-8')
Von Dü
>>>
Edit:
>>> print '\xc3\x96berg' # no unicode identifier, works as expected because it's an UTF-8 encoded string
Öberg
>>> print u'\xc3\x96berg' # has unicode identifier, means print uses the unicode charset now, outputs weird stuff
Ãberg
# Look at the differing object types:
>>> type('\xc3\x96berg')
<type 'str'>
>>> type(u'\xc3\x96berg')
<type 'unicode'>
>>> '\xc3\x96berg'.decode('utf-8') # this command converts from UTF-8 to unicode, look at the unicode identifier in the output
u'\xd6berg'
>>> unicode('\xc3\x96berg', 'utf-8') # this does the same thing
u'\xd6berg'
>>> unicode(u'foo bar', 'utf-8') # trying to convert a unicode string to unicode will fail as expected
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
TypeError: decoding Unicode is not supported

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