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How to write header row with csv.DictWriter?
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Edit:
In 2.7 / 3.2 there is a new writeheader() method. Also, John Machin's answer provides a simpler method of writing the header row.
Simple example of using the writeheader() method now available in 2.7 / 3.2:
from collections imp...
What are the differences between json and simplejson Python modules?
... an up to date Python. The built-in (great plus!!!) Json library in Python 2.7 is as fast as simplejson and has less refused-to-be-fixed unicode bugs. See answer stackoverflow.com/a/16131316/78234
– Tal Weiss
May 13 '13 at 13:48
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“INSERT IGNORE” vs “INSERT … ON DUPLICATE KEY UPDATE”
...th many rows, I want to skip duplicate entries that would otherwise cause failure. After some research, my options appear to be the use of either:
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How can I install pip on Windows?
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Python 2.7.9+ and 3.4+
Good news! Python 3.4 (released March 2014) and Python 2.7.9 (released December 2014) ship with Pip. This is the best feature of any Python release. It makes the community's wealth of libraries accessible to ...
More elegant way of declaring multiple variables at the same time
...doesn't really help to explain how the routine works.
Apparently Python 2.7 has dictionary comprehensions, which would make for an extremely concise way to implement that function. This is left as an exercise to the reader, since I don't have Python 2.7 installed :)
You can also combine some fu...
Need for predictable random generator
...ndomness in small runs of some games is undesirable -- it does seem too unfair for some use cases.
I wrote a simple Shuffle Bag like implementation in Ruby and did some testing. The implementation did this:
If it still seems fair or we haven't reached a threshold of minimum rolls, it returns a...
What is the most efficient string concatenation method in python?
... up to a direct '+' operation or a ''.join(). But guess what? On my Python 2.7.5 system, the string interpolation operator rules them all and string.format() is the worst performer:
# concatenate_test.py
from __future__ import print_function
import timeit
domain = 'some_really_long_example.com'
l...
Understanding generators in Python
...a slightly different technique, namely o.next() instead of next(o). Python 2.7 has next() call .next so you need not use the following in 2.7:
>>> g = (n for n in range(3, 5))
>>> g.next()
3
share
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Python : List of dict, if exists increment a dict value, if not append a new dict
...mple then becomes:
from collections import Counter # available in Python 2.7 and newer
urls_d = Counter(list_of_urls)
If you really need to do it the way you showed, the easiest and fastest way would be to use any one of these three examples, and then build the one you need.
from collections i...
Difference between add(), replace(), and addToBackStack()
What is the main difference between calling these methods:
9 Answers
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