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What's the simplest way to subtract a month from a date in Python?
...with param month doesn't work but months works In [23]: created_datetime__lt - relativedelta(months=1) Out[23]: datetime.datetime(2016, 11, 29, 0, 0, tzinfo=<StaticTzInfo 'Etc/GMT-8'>) In [24]: created_datetime__lt - relativedelta(month=1) Out[24]: datetime.datetime(2016, 1, 29,...
Should import statements always be at the top of a module?
...ent libraries, don't break if an optional library is not installed.
In the __init__.py of a plugin, which might be imported but not actually used. Examples are Bazaar plugins, which use bzrlib's lazy-loading framework.
shar...
Count how many records are in a CSV Python?
...
You need to count the number of rows:
row_count = sum(1 for row in fileObject) # fileObject is your csv.reader
Using sum() with a generator expression makes for an efficient counter, avoiding storing the whole file in memory.
If you already read 2 rows to start ...
How do I select a random value from an enumeration?
...ve an array of all values. Then select a random array item.
static Random _R = new Random ();
static T RandomEnumValue<T> ()
{
var v = Enum.GetValues (typeof (T));
return (T) v.GetValue (_R.Next(v.Length));
}
Test:
for (int i = 0; i < 10; i++) {
var value = RandomEnumValue&l...
Creating C formatted strings (not printing them)
...nts are ignored by the function.
Example:
// Allocates storage
char *hello_world = (char*)malloc(13 * sizeof(char));
// Prints "Hello world!" on hello_world
sprintf(hello_world, "%s %s!", "Hello", "world");
share
...
How to call a Parent Class's method from Child Class in Python?
... for calling parent method.
If Foo class inherits from Bar, then from Bar.__init__ can be invoked from Foo via super().__init__():
class Foo(Bar):
def __init__(self, *args, **kwargs):
# invoke Bar.__init__
super().__init__(*args, **kwargs)
...
top -c command in linux to filter processes listed based on processname
... to get pid's of matching command lines:
top -c -p $(pgrep -d',' -f string_to_match_in_cmd_line)
top -p expects a comma separated list of pids so we use -d',' in pgrep. The -f flag in pgrep makes it match the command line instead of program name.
...
Bash continuation lines
...here document. (Line terminators will still remain, though.)
cat <<-____HERE
continuation
lines
____HERE
See also http://ss64.com/bash/syntax-here.html
If you need to preserve some, but not all, leading whitespace, you might use something like
sed 's/^ //' <<____HERE
Th...
android studio 0.4.2: Gradle project sync failed error
...me .gradle file out of the way". I tried changing its name for example to "___build.gradle" and it didn't work. What did you mean to?
– Ángel Carlos del Pozo Muela
Jan 17 '14 at 7:42
...
How to run a PowerShell script from a batch file
...y Bypass Invoke-WebRequest https://www.example.com/example.ics -OutFile C:\_my\script.ics' -Verb RunAs}"; or powershell -Command "Invoke-WebRequest https://www.example.com/example.ics -OutFile c:\_my\file.ics", or using the -File option to same in a .ps1 file, or (New-Object Net.WebClient).DownloadF...