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Can iterators be reset in Python?
...ary data needs to be
stored). In general, if one iterator
uses most or all of the data before
another iterator starts, it is faster
to use list() instead of tee().
Basically, tee is designed for those situation where two (or more) clones of one iterator, while "getting out of sync" with ea...
Django in / not in query
...e(); Tbl2.objects.filter(id__in=IDs') This did not work because IDs is actually a QuerySet object. When I deleted the rows it originated from, it no longer worked with other queries. The solution is Tbl2.objects.filter(id__in=list(IDs)) -- turn it into a list
– Dakusan
...
Are there any standard exit status codes in Linux?
...ld died with 11" */
}
How are you determining the exit status? Traditionally, the shell only stores an 8-bit return code, but sets the high bit if the process was abnormally terminated.
$ sh -c 'exit 42'; echo $?
42
$ sh -c 'kill -SEGV $$'; echo $?
Segmentation fault
139
$ expr 139 - 128
11
I...
How to install MySQLdb (Python data access library to MySQL) on Mac OS X?
...
Update for those using Python3:
You can simply use conda install mysqlclient to install the libraries required to use MySQLdb as it currently exists. The following SO question was a helpful clue: Python 3 ImportError: No module named 'ConfigParser' . Installing mysqlclient will install...
How do I execute inserts and updates in an Alembic upgrade script?
...s is useful for simple migrations.
Use the models and session as you normally would in your application.
"""create teams table
Revision ID: 169ad57156f0
Revises: 29b4c2bfce6d
Create Date: 2014-06-25 09:00:06.784170
"""
revision = '169ad57156f0'
down_revision = '29b4c2bfce6d'
from alembic imp...
How to use ng-repeat without an html element
I need to use ng-repeat (in AngularJS) to list all of the elements in an array.
8 Answers
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What is external linkage and internal linkage?
... a translation unit. This is the source file from your implementation plus all the headers you #included in it.
Internal linkage refers to everything only in scope of a translation unit.
External linkage refers to things that exist beyond a particular translation unit. In other words, accessible ...
CURL alternative in Python
I have a cURL call that I use in PHP:
7 Answers
7
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More elegant way of declaring multiple variables at the same time
...variables with Boolean values is the best way to write your routine (especially if they really have one-letter names :)
Depending on what you're doing, it may make sense to use a dictionary instead. For example, if you want to set up Boolean preset values for a set of one-letter flags, you could d...
How to retry after exception?
I have a loop starting with for i in range(0, 100) . Normally it runs correctly, but sometimes it fails due to network conditions. Currently I have it set so that on failure, it will continue in the except clause (continue on to the next number for i ).
...