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Generating CSV file for Excel, how to have a newline inside a value
...ixed the leading spaces issue in the question, I typed the CSV example manually and didn't copy-paste from a real file, the real file doesn't include those spaces, good catch.
– Nir
Aug 10 '09 at 7:41
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Why is “if not someobj:” better than “if someobj == None:” in Python?
...a __nonzero__ special method (as do numeric built-ins, int and float), it calls this method. It must either return a bool value which is then directly used, or an int value that is considered False if equal to zero.
Otherwise, if the object has a __len__ special method (as do container built-ins, li...
What is a StackOverflowError?
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Parameters and local variables are allocated on the stack (with reference types, the object lives on the heap and a variable in the stack references that object on the heap). The stack typically lives at the upper end of your address space and as it is used up...
Inheritance and Overriding __init__ in python
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The book is a bit dated with respect to subclass-superclass calling. It's also a little dated with respect to subclassing built-in classes.
It looks like this nowadays:
class FileInfo(dict):
"""store file metadata"""
def __init__(self, filename=None):
super(FileInfo,...
Why is the order in dictionaries and sets arbitrary?
...der:
>>> {'bar': None, 'foo': None}
{'foo': None, 'bar': None}
All slots except 3 and 4 are empty, looping over the table first lists slot 3, then slot 4, so 'foo' is listed before 'bar'.
bar and baz, however, have hash values that are exactly 8 apart and thus map to the exact same slot...
How to convert a string of bytes into an int?
...to handle that if you know the type of each item.
– Joshua Olson
Jan 9 '14 at 18:12
2
"L" is actu...
Programmatically relaunch/recreate an activity?
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recreate method call repaetdedly fourcefully close the app
– SAndroidD
May 22 '14 at 8:47
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Is there any way to change input type=“date” format?
...riting Chrome, Edge, Firefox, and Opera have date support (see here). They all display a date picker and format the text in the input field.
Desktop devices
For Chrome, Firefox, and Opera, the formatting of the input field's text is based on the browser's language setting. For Edge, it is based on...
Define a lambda expression that raises an Exception
...ur goal is to avoid a def, this obviously doesn't cut it. It does, however allow you to conditionally raise exceptions, e.g.:
y = lambda x: 2*x if x < 10 else raise_(Exception('foobar'))
Alternatively you can raise an exception without defining a named function. All you need is a strong stom...
Check if $_POST exists
...sts and if it does, print it inside another string, if not, don't print at all.
14 Answers
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