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How to get string objects instead of Unicode from JSON?
...unicode strings, then recurses through the entire decoded value to convert all strings to byte strings. This has a couple of undesirable effects:
A copy of the entire decoded structure gets created in memory
If your JSON object is really deeply nested (500 levels or more) then you'll hit Python's ...
Local variables in nested functions
...ints to the local variable cage in the get_petters function.
When you actually call the function, that closure is then used to look at the value of cage in the surrounding scope at the time you call the function. Here lies the problem. By the time you call your functions, the get_petters function i...
How exactly does a generator comprehension work?
... generator expression is like a list comprehension, but instead of finding all the items you're interested and packing them into list, it waits, and yields each item out of the expression, one by one.
>>> my_list = [1, 3, 5, 9, 2, 6]
>>> filtered_list = [item for item in my_list i...
What is the iPad user agent?
... This answer is incorrect. From iOS 13 there is now no mention of iPad at all.
– CpnCrunch
Dec 16 '19 at 18:51
See th...
Python (and Python C API): __new__ versus __init__
...vs immutable types.
__new__ accepts a type as the first argument, and (usually) returns a new instance of that type. Thus it is suitable for use with both mutable and immutable types.
__init__ accepts an instance as the first argument and modifies the attributes of that instance. This is inappropr...
Importing from a relative path in Python
...his method is still commonly used in some situations, where you aren't actually ever 'installing' your package. For example, it's popular with Django users.
You can add Common/ to your sys.path (the list of paths python looks at to import things):
import sys, os
sys.path.append(os.path.join(os.p...
How to flush output of print function?
...e)
On Python 2 you'll have to do
import sys
sys.stdout.flush()
after calling print. By default, print prints to sys.stdout (see the documentation for more about file objects).
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Scala: What is a TypeTag and how do I use it?
All I know about TypeTags is that they somehow replaced Manifests. Information on the Internet is scarce and doesn't provide me with a good sense of the subject.
...
__lt__ instead of __cmp__
...ttributes of the new class it's decorating (the result might be microscopically faster at runtime, at equally minute cost in terms of memory).
Of course, if your class has some particularly fast way to implement (e.g.) __eq__ and __ne__, it should define them directly so the mixin's versions are no...
python: Change the scripts working directory to the script's own directory
... __file__ fails in "frozen" programs (created using py2exe, PyInstaller, cx_Freeze). sys.argv[0] works. @ChrisDown: If you want to follow symlinks; os.path.realpath() could be used.
– jfs
Apr 5 '14 at 20:12
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