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List of lists changes reflected across sublists unexpectedly
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When you write [x]*3 you get, essentially, the list [x, x, x]. That is, a list with 3 references to the same x. When you then modify this single x it is visible via all three references to it:
x = [1] * 4
l = [x] * 3
print(f"id(x): {id(x)}")
# id(x): 1405608979...
Python Unicode Encode Error
...80\x80abcd\xde\xb4'
>>> u.encode('ascii')
Traceback (most recent call last):
File "<stdin>", line 1, in ?
UnicodeEncodeError: 'ascii' codec can't encode character '\ua000' in position 0: ordinal not in range(128)
>>> u.encode('ascii', 'ignore')
'abcd'
>>> u.encode(...
How to manage local vs production settings in Django?
...velopment and production. And every developer has a different code base.I call anti-pattern here.
– pydanny
Jan 31 '13 at 16:25
8
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Transposing a NumPy array
...of a 1D array is still a 1D array! (If you're used to matlab, it fundamentally doesn't have a concept of a 1D array. Matlab's "1D" arrays are 2D.)
If you want to turn your 1D vector into a 2D array and then transpose it, just slice it with np.newaxis (or None, they're the same, newaxis is just mor...
Determine the type of an object?
...object, and isinstance() to check an object’s type against something. Usually, you want to use isistance() most of the times since it is very robust and also supports type inheritance.
To get the actual type of an object, you use the built-in type() function. Passing an object as the only param...
How to import a module given the full path?
... path from its cache. In my case I aimed at creating a plugin system where all plugins implement a specific classX. I ended up using SourceFileLoader, note that its deprecation is controversial.
– ComFreek
Jul 3 '15 at 17:18
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How can I check for Python version in a program that uses new language features?
...rom the question that needed addressing is that a program must be syntactically correct for that version of python to even begin executing, so using new syntax precludes a program from starting on older versions of the interpreter. eval works around that
– Autoplectic
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JavaScript for detecting browser language preference [duplicate]
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I think the main problem here is that the browser settings don't actually affect the navigator.language property that is obtained via javascript.
What they do affect is the HTTP 'Accept-Language' header, but it appears this value is not available through javascript at all. (Probably why @and...
Get name of object or class
...(function(){}); new myclass prints myclass {}
– Hugh Allen
May 26 '14 at 4:09
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Getting visitors country from their IP
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why im getting unknow all the time with every ip ? , used same code.
– echo_Me
Feb 18 '14 at 18:12
1
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