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Django in / not in query
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table1.objects.exclude(id__in=
table2.objects.filter(your_condition).values_list('id', flat=True))
The exclude function works like the Not operator you where asking for. The attribute flat = True tells to table2 query to return the value_list a...
Python Nose Import Error
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You've got an __init__.py in your top level directory. That makes it a package. If you remove it, your nosetests should work.
If you don't remove it, you'll have to change your import to import dir.foo, where dir is the name of your dire...
“Large data” work flows using pandas
...fields to a specific group, and defines
# what you want to have as data_columns.
# you might want to create a nice class wrapping this
# (as you will want to have this map and its inversion)
group_map = dict(
A = dict(fields = ['field_1','field_2',.....], dc = ['field_1',....,'field_...
How to print a dictionary line by line in Python?
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I do print(json.dumps(cars, indent=4, ensure_ascii=False)) because otherwise non-ASCII characters are unreadable.
– Boris
Apr 22 at 16:36
add a ...
Bin size in Matplotlib (Histogram)
...width in this example could be found by: (data.max() - data.min()) / number_of_bins_you_want. The + binwidth could be changed to just 1 to make this a more easily understood example.
– Jarad
Jan 22 '18 at 17:31
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How can I access “static” class variables within class methods in Python?
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Why not just Foo.bar, instead of self.__class__.bar?
– mk12
Sep 13 '09 at 20:59
15
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悬浮窗使用指导 · App Inventor 2 中文网
...它应用上层，先测试本应用内。
放竖直布局 竖直布局_浮窗，宽 180、高自动、背景白色、可见为假；里面放标签（文本“工具面板”）和按钮 按钮_关闭（文本“关闭”）。
使用本节完整代码，不与其它例子的初始化事件叠...
Why use apparently meaningless do-while and if-else statements in macros?
...mi-colon. Should the user view code not needing one...
doSomething(1) ;
DO_SOMETHING_ELSE(2) // <== Hey? What's this?
doSomethingElseAgain(3) ;
This means the user expects the compiler to produce an error if the semi-colon is absent.
But the real real good reason is that at some time, the ma...
micro:bit 实验03 - 做一块实时温度看板 · App Inventor 2 中文网
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命名
关键属性
标签
标签_温度
字号 48、粗体、居中，文本「–」
标签
标签_单位
文本「℃」
滑动条
滑动条_周期
最小值 1、最大值 10、初始 1（单位...
Dynamic variable names in Bash
...ay, with command names as keys.
# Requires bash 4, though
declare -A magic_variable=()
function grep_search() {
magic_variable[$1]=$( ls | tail -1 )
echo ${magic_variable[$1]}
}
If you can't use associative arrays (e.g., you must support bash 3), you can use declare to create dynamic var...