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Does Python support short-circuiting?
...ent, but you could also state things very succinctly:
In [171]: name = raw_input('Enter Name: ') or '<Unkown>'
Enter Name:
In [172]: name
Out[172]: '<Unkown>'
In other words, if the return value from raw_input is true (not an empty string), it is assigned to name (nothing changes); ...
Python list subtraction operation
...t to use the - infix syntax, you can just do:
class MyList(list):
def __init__(self, *args):
super(MyList, self).__init__(args)
def __sub__(self, other):
return self.__class__(*[item for item in self if item not in other])
you can then use it like:
x = MyList(1, 2, 3, 4...
how to delete all cookies of my website in php
...ill unset all of the cookies for your domain:
// unset cookies
if (isset($_SERVER['HTTP_COOKIE'])) {
$cookies = explode(';', $_SERVER['HTTP_COOKIE']);
foreach($cookies as $cookie) {
$parts = explode('=', $cookie);
$name = trim($parts[0]);
setcookie($name, '', time()-...
Why can't I use a list as a dict key in python?
...le, it'll work correctly with classes that have a custom comparison method __eq__. But if you convert them to strings, everything is compared by its string representation.
– Aran-Fey
May 20 '18 at 12:50
...
What is the difference between old style and new style classes in Python?
...o the concept of type:
if x is an instance of an old-style class, then x.__class__
designates the class of x, but type(x) is always <type
'instance'>.
This reflects the fact that all old-style instances, independently of
their class, are implemented with a single built-in type, c...
Where is a complete example of logging.config.dictConfig?
...
How about here!
LOGGING_CONFIG = {
'version': 1,
'disable_existing_loggers': True,
'formatters': {
'standard': {
'format': '%(asctime)s [%(levelname)s] %(name)s: %(message)s'
},
},
'handlers': {
...
html select option separator
...on>First</option>
</optgroup>
<optgroup label="_________">
<option>Second</option>
<option>Third</option>
</optgroup>
</select>
disabled option (a bit better):
<select>
<option>Fir...
What is the difference between join and merge in Pandas?
...andas as pd
left = pd.DataFrame({'key': ['foo', 'bar'], 'val': [1, 2]}).set_index('key')
right = pd.DataFrame({'key': ['foo', 'bar'], 'val': [4, 5]}).set_index('key')
left.join(right, lsuffix='_l', rsuffix='_r')
val_l val_r
key
foo 1 4
bar 2 5
The same functi...
Specifying rails version to use when creating a new application
...option to create a new application using an older version of Rails.
rails _2.1.0_ new myapp
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When should iteritems() be used instead of items()?
... more like a set (which you'd expect from a dict).
Simple example:
common_keys = list(dict_a.viewkeys() & dict_b.viewkeys())
Will give you a list of the common keys, but again, in Python 3.x - just use .keys() instead.
Python 3.x has generally been made to be more "lazy" - i.e. map is now e...