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Using Python String Formatting with Lists
I construct a string s in Python 2.6.5 which will have a varying number of %s tokens, which match the number of entries in list x . I need to write out a formatted string. The following doesn't work, but indicates what I'm trying to do. In this example, there are three %s tokens and the list ...
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...
What are some good Python ORM solutions? [closed]
...ally a JavaScript front-end from the client-side (browser) that talks to a Python web service on the back-end. So, I really need something fast and lightweight on the back-end that I can implement using Python that then speaks to the PostgreSQL DB via an ORM (JSON to the browser).
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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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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...
How can I give eclipse more memory than 512M?
... maximum value that's dependent on your system. Here's that section on my Linux box:
-vmargs
-Dosgi.requiredJavaVersion=1.5
-XX:MaxPermSize=512m
-Xms512m
-Xmx1024m
And here's that section on my Windows box:
-vmargs
-Xms256m
-Xmx1024m
But, I've failed at setting it higher than 1024 megs. If an...
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...
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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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 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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