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How to “test” NoneType in python?
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Why this works?
Since None is the sole singleton object of NoneType in Python, we can use is operator to check if a variable has None in it or not.
Quoting from is docs,
The operators is and is not test for object identity: x is y is true if and only if x and y are the same object. x is not...
UnicodeEncodeError: 'ascii' codec can't encode character u'\xa0' in position 20: ordinal not in rang
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You need to read the Python Unicode HOWTO. This error is the very first example.
Basically, stop using str to convert from unicode to encoded text / bytes.
Instead, properly use .encode() to encode the string:
p.agent_info = u' '.join((agent_c...
Return first N key:value pairs from dict
...urn list(islice(iterable, n))
See it working online: ideone
Update for Python 3.6
n_items = take(n, d.items())
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How do I save and restore multiple variables in python?
...created here...
# Saving the objects:
with open('objs.pkl', 'w') as f: # Python 3: open(..., 'wb')
pickle.dump([obj0, obj1, obj2], f)
# Getting back the objects:
with open('objs.pkl') as f: # Python 3: open(..., 'rb')
obj0, obj1, obj2 = pickle.load(f)
If you have a lot of data, you can...
Check whether a path is valid in Python without creating a file at the path's target
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Call the is_path_exists_or_creatable() function defined below.
Strictly Python 3. That's just how we roll.
A Tale of Two Questions
The question of "How do I test pathname validity and, for valid pathnames, the existence or writability of those paths?" is clearly two separate questions. Both are...
python: how to send mail with TO, CC and BCC?
... smtplib.SMTP does not send lists as to addresses. At least not on python 2.7.2
– LostMohican
Apr 5 '12 at 8:06
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Convert string in base64 to image and save on filesystem in Python
...e data using the base64 codec, and then write it to the filesystem.
# In Python 2.7
fh = open("imageToSave.png", "wb")
fh.write(img_data.decode('base64'))
fh.close()
# or, more concisely using with statement
with open("imageToSave.png", "wb") as fh:
fh.write(img_data.decode('base64'))
Moder...
What is :: (double colon) in Python when subscripting sequences?
I know that I can use something like string[3:4] to get a substring in Python, but what does the 3 mean in somesequence[::3] ?
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How can I create a copy of an object in Python?
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How can I create a copy of an object in Python?
So, if I change values of the fields of the new object, the old object should not be affected by that.
You mean a mutable object then.
In Python 3, lists get a copy method (in 2, you'd use a slice to make a copy):
&g...
How to read a text file into a list or an array with Python
I am trying to read the lines of a text file into a list or array in python. I just need to be able to individually access any item in the list or array after it is created.
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