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Best way to remove '\xad' in Python?

I'm trying to build a corpus from the .txt file found at this link.
I believe the instances of \xad are supposedly 'soft-hyphens', but do not appear to be read correctly under UTF-8 encoding. I've tried encoding the .txt file as iso8859-15, using the code:
with open('Harry Potter 3 - The Prisoner Of Azkaban.txt', 'r',
encoding='iso8859-15') as myfile:
data=myfile.read().replace('\n', '')
data2 = data.split(' ')
This returns an array of 'words', but '\xad' remains attached to many entries in data2. I've tried
data_clean = data.replace('\\xad', '')
and
data_clean = data.replace('\\xad|\\xad\\xad','')
but this doesn't seem to remove the instances of '\xad'. Has anyone ran into a similar problem before? Ideally I'd like to encode this data as UTF-8 to avail of the nltk library, but it won't read the file with UTF-8 encoding as I get the following error:
UnicodeDecodeError: 'utf-8' codec can't decode byte 0xad in position 471: invalid start byte
Any help would be greatly appreciated!
Additional context: This is a recreational project with the aim of being able to generate stories based on the txt file. Everything I've generated thus far has been permeated with '\xad', which ruins the fun!

Your file almost certainly has actual U+00AD soft-hyphen characters in it.
These are characters that mark places where a word could be split when fitting lines to a page. The idea is that the soft hyphen is invisible if the word doesn't need to be split, but printed the same as a U+2010 normal hyphen if it does.
Since you don't care about rendering this text in a book with nicely flowing text, you're never going to hyphenate anything, so you just want to remove these characters.
The way to do this is not to fiddle with the encoding. Just remove them from the Unicode text, using whichever of these you find most readable:
data = data.replace('\xad', '')
data = data.replace('\u00ad', '')
data = data.replace('\N{SOFT HYPHEN}', '')
Notice the single backslash. We're not replacing a literal backslash, x, a, d, we're replacing a literal soft-hyphen character, that is, the character whose code point is hex 0xad.
You can either do this to the whole file before splitting into words, or do it once per word after splitting.
Meanwhile, you seem to be confused about what encodings are and what to do with them:
I've tried encoding the .txt file as iso8859-15
No, you've tried decoding the file as ISO-8859-15. It's not clear why you tried ISO-8859-15 in the first place. But, since the ISO-8859-15 encoding for the character '\xad' is the byte b'\xad', maybe that's correct.
Ideally I'd like to encode this data as UTF-8 to avail of the nltk library
But NLTK doesn't want UTF-8 bytes, it wants Unicode strings. You don't need to encode it for that.
Plus, you're not trying to encode your Unicode text to UTF-8, you're trying to decode your bytes from UTF-8. If that's not what those bytes are… if you're lucky, you'll get an error like this one; if not, you'll get mojibake that you don't notice until you've screwed up a 500GB corpus and thrown away the original data.1
1. UTF-8 is specifically designed so you'll get early errors whenever possible. In this case, reading ISO-8859-15 text with soft hyphens as if it were UTF-8 raises exactly the error you're seeing, but reading UTF-8 text with soft hyphens as if it were ISO-8859-15 will silently succeed, but with an extra 'Â' character before each soft hyphen. The error is usually more helpful.

Python decoding issue with Chinese characters

I'm using Python 3.5, and I'm trying to take a block of byte text that may or may not contain special Chinese characters and output it to a file. It works for entries that do not contain Chinese characters, but breaks when they do. The Chinese characters are always a person's name, and are always in addition to the English spelling of their name. The text is JSON formatted and needs to be decoded before I can load it. The decoding seems to go fine and doesn't give me any errors. When I try and write the decoded text to a file it gives me the following error message:
UnicodeEncodeError: 'charmap' codec can't encode characters in position 14-18: character maps to undefined
Here is an example of the raw data that I get before I do anything to it:
b' "isBulkRecipient": "false",\r\n "name": "Name in, English \xef'
b'\xab\x62\xb6\xe2\x15\x8a\x8b\x8a\xee\xab\x89\xcf\xbc\x8a",\r\n
Here is the code that I am using:
recipientData = json.loads(recipientContent.decode('utf-8', 'ignore'))
recipientName = recipientData['signers'][0]['name']
pprint(recipientName)
with open('envelope recipient list.csv', 'a', newline='') as fp:
a = csv.writer(fp, delimiter=',')
csvData = [[recipientName]]
a.writerows(csvData)
The recipientContent is obtained from an API call. I do not need to have the Chinese characters in the output file. Any advice will be greatly appreciated!
Update:
I've been doing some manual workarounds for each entry that breaks, and came other entries that didn't contain Chinese special characters, but had them from other languages, and the broke the program as well. The special characters are only in the name field. So a name could be something like "Ałex" where it is a mixture of normal and special characters. Before i decode the string that contains this information i am able to print it out to the screen and it looks like this: b'name": "A\xc5ex",\r\n
But after i decode it into utf-8 it will give me an error if i try to output it. The error message is: UnicodeEncodeError: 'charmap' codec can't encode character 'u0142' in position 2- character maps to -undefined-
I looked up what \u0142 was and it is the ł special character.

The error you're getting is when you're writing to the file.
In Python 3.x, when you open() in text mode (the default) without specifying an encoding=, Python will use an encoding most suitable to your locale or language settings.
If you're on Windows, this will use the charmap codec to map to your language encoding.
Although you could just write bytes straight to a file, you're doing the right thing by decoding it first. As others have said, you should really decode using the encoding specified by the web server. You could also use Python Requests module, which does this for you. (You example doesn't decode as UTF-8, so I assume your example isn't correct)
To solve your immediate error, simply pass an encoding to open(), which supports the characters you have in your data. Unicode in UTF-8 encoding is the obvious choice. Therefore, you should change your code to read:
with open('envelope recipient list.csv', 'a', encoding='utf-8', newline='') as fp:

Warning: shotgun solution ahead
Assuming you just want to get rid of all foreign character in all your file ( that is they are not important for your future processing of all other fields), you can simply ignore all non ascii characters
recipientData = json.loads(recipientContent.decode('utf-8', 'ignore'))
by
recipientData = json.loads(recipientContent.decode('ascii', 'ignore'))
like this you remove all non ascii characters before future processing.
I called it shotgun solution because it might not work correctly under certain circumstances:
Obviously if non ascii characters are needed to keep for future use
If b'\' or b" characters appears for example from part of an utf-16 character.

Add this line to your code :
from __future__ import unicode_literals

django + unicode constant errors

I built a django site last year that utilises both a dashboard and an API for a client.
They are, on occasion, putting unicode information (usually via a Microsoft keyboard and a single quote character!) into the database.
It's fine to change this one instance for everything, but what I constantly get is something like this error when a new character is added that I haven't "converted":
UnicodeDecodeError at /xx/xxxxx/api/xxx.json
'ascii' codec can't decode byte 0xeb in position 0: ordinal not in range(128)
The issue is actually that I need to be able to convert this unicode (from the model) into HTML.
# if a char breaks the system, replace it here (duplicate line)
text = unicode(str(text).replace('\xa3', '£'))
I duplicate this line here, but it just breaks otherwise.
Tearing my hair out because I know this is straight forward and I'm doing something remarkably silly somewhere.
Have searched elsewhere and realised that while my issue is not new, I can't find the answer elsewhere.

I assume that text is unicode (which seems a safe assumption, as \xa3 is the unicode for the £ character).
I'm not sure why you need to encode it at all, seeing as the text will be converted to utf-8 on output in the template, and all browsers are perfectly capable of displaying that. There is likely another point further down the line where something (probably your code, unfortunately) is assuming ASCII, and the implicit conversion is breaking things.
In that case, you could just do this:
text = text.encode('ascii', 'xmlcharrefreplace')
which converts the non-ASCII characters into HTML/XML entities like £.

Tell the JSON-decoder that it shall decode the json-file as unicode. When using the json module directly, this can be done using this code:
json.JSONDecoder(encoding='utf8').decode(
json.JSONEncoder(encoding='utf8').encode('blä'))
If the JSON decoding takes place via some other modules (django, ...) maybe you can pass the information through this other module into the json stuff.

Python Unicode CSV export (using Django)

I'm using a Django app to export a string to a CSV file. The string is a message that was submitted through a front end form. However, I've been getting this error when a unicode single quote is provided in the input.
UnicodeEncodeError: 'ascii' codec can't encode character u'\u2019'
in position 200: ordinal not in range(128)
I've been trying to convert the unicode to ascii using the code below, but still get a similar error.
UnicodeEncodeError: 'ascii' codec can't encode characters in
position 0-9: ordinal not in range(128)
I've sifted through dozens of websites and learned a lot about unicode, however, I'm still not able to convert this unicode to ascii. I don't care if the algorithm removes the unicode characters. The commented lines indicate some various options I've tried, but the error persists.
import csv
import unicodedata
...
#message = unicode( unicodedata.normalize(
# 'NFKD',contact.message).encode('ascii','ignore'))
#dmessage = (contact.message).encode('utf-8','ignore')
#dmessage = contact.message.decode("utf-8")
#dmessage = "%s" % dmessage
dmessage = contact.message
csv_writer.writerow([
dmessage,
])
Does anyone have any advice in removing unicode characters to I can export them to CSV? This seemingly easy problem has kept my head spinning. Any help is much appreciated.
Thanks,
Joe

You can't encode the Unicode character u'\u2019' (U+2019 Right Single Quotation Mark) into ASCII, because ASCII doesn't have that character in it. ASCII is only the basic Latin alphabet, digits and punctuation; you don't get any accented letters or ‘smart quotes’ like this character.
So you will have to choose another encoding. Now normally the sensible thing to do would be to export to UTF-8, which can hold any Unicode character. Unfortunately for you if your target users are using Office (and they probably are), they're not going to be able to read UTF-8-encoded characters in CSV. Instead Excel will read the files using the system default code page for that machine (also misleadingly known as the ‘ANSI’ code page), and end up with mojibake like ’ instead of ’.
So that means you have to guess the user's system default code page if you want the characters to show up correctly. For Western users, that will be code page 1252. Users with non-Western Windows installs will see the wrong characters, but there's nothing you can do about that (other than organise a letter-writing campaign to Microsoft to just drop the stupid nonsense with ANSI already and use UTF-8 like everyone else).
Code page 1252 can contain U+2019 (’), but obviously there are many more characters it can't represent. To avoid getting UnicodeEncodeError for those characters you can use the ignore argument (or replace to replace them with question marks).
dmessage= contact.message.encode('cp1252', 'ignore')
alternatively, to give up and remove all non-ASCII characters, so that everyone gets an equally bad experience regardless of locale:
dmessage= contact.message.encode('ascii', 'ignore')

Encoding is a pain, but if you're working in django have you tried smart_unicode(str) from django.utils.encoding? I find that usually does the trick.
The only other option I've found is to use the built-in python encode() and decode() for strings, but you have to specify the encoding for those and honestly, it's a pain.

[caveat: I'm not a djangoist; django may have a better solution].
General non-django-specific answer:
If you have a smallish number of known non-ASCII characters and there are user-acceptable ASCII equivalents for them, you can set up a translation table and use the unicode.translate method:
smashcii = {
0x2019 : u"'",
# etc
#
smashed = input_string.translate(smashcii)

Python Encoding issue

Why am I getting this issue? and how do I resolve it?
UnicodeDecodeError: 'utf8' codec can't decode byte 0x92 in position 24: unexpected code byte
Thank you

Somewhere, perhaps subtly, you are asking Python to turn a stream of bytes into a "string" of characters.
Don't think of a string as "bytes". A string is a list of numbers, each number having an agreed meaning in Unicode. (#65 = Latin Capital A. #19968 = Chinese Character "One"/"First") .
There are many methods of encoding a list of Unicode entities into a stream of bytes. Python is assuming your stream of bytes is the result of a particular such method, called "UTF-8".
However, your stream of bytes has data that does not correspond to that method. Thus the error is raised.
You need to figure out the encoding of the stream of bytes, and tell Python that encoding.
It's important to know if you're using Python 2 or 3, and the code leading up to this exception to see where your bytes came from and what the appropriate way to deal with them is.
If it's from reading a file, you can explicity deal with the bytes read. But you must be sure of the file encoding.
If it's from a string that is part of your source code, then Python is assuming the "wrong thing" about your source files... perhaps $LC_ALL or $LANG needs to be set. This is a good time to firmly understand the concept of encoding, and how text editors choose an encoding to write, and what is standard for your language and operating system.

In addition to what Joe said, chardet is a useful tool to detect encoding of the source data.

Somewhere you have a plain string encoded as "Windows-1252" (or "cp1252") containing a "RIGHT SINGLE QUOTATION MARK" (’) instead of an APOSTROPHE ('). This could come from a file you read, or even in a Python source file of yours; you could be running Python 2.x and have a # -*- coding: utf8 -*- line somewhere near the script's beginning, or you could be running Python 3.x.
You don't give enough data; however, somewhere you have a cp1252-encoded string, which you try (explicitly or implicitly) to decode to unicode as utf-8. This won't work.
Give us more info, and we'll try again to help you.
Joe Koberg's answer reminded me of an older answer of mine, which some people have found helpful: Python UnicodeDecodeError - Am I misunderstanding encode?