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Can I make the foreign key field optional in Django model
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Sure, just add blank=True, null=True for each field that you want to remain optional like
subject = models.ForeignKey(subjects, blank=True, null=True)
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setup cron tab to specific time of during weekdays
...script at certain times of the day and on some specific days of the week. For example, we want to setup a cron job that runs the script with the following sequence:
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ggplot: How to increase spacing between faceted plots?
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This works without the grid package. In my experience the x labels of two side-by-side plots often overlap (the greatest label on the lhs and the smallest label on the rhs). One solution to fix the output is to ggsave with a greate...
How to spread django unit tests over multiple files?
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The behavior has changed in Django 1.6, so there is no longer a need to create a package. Just name your files test*.py.
From Django 1.7 documentation
When you run your tests, the default behavior of the test utility is
to find ...
Creating an instance of class
...1 */ Foo* foo1 = new Foo ();
Creates an object of type Foo in dynamic memory. foo1 points to it. Normally, you wouldn't use raw pointers in C++, but rather a smart pointer. If Foo was a POD-type, this would perform value-initialization (it doesn't apply here).
/* 2 */ Foo* foo2 = new Foo;
Id...
Assign variables to child template in {% include %} tag Django
...uggested, it's pretty simple:
{% include "subject_file_upload.html" with form=form foo=bar %}
The documentation for include mentions this. It also mentions that you can use only to render the template with the given variables only, without inheriting any other variables.
Thank you @Besnik
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Objective-C for Windows
What would be the best way to write Objective-C on the Windows platform?
13 Answers
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Get exception description and stack trace which caused an exception, all as a string
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See the traceback module, specifically the format_exc() function. Here.
import traceback
try:
raise ValueError
except ValueError:
tb = traceback.format_exc()
else:
tb = "No error"
finally:
print tb
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Remove border from buttons
...rt my own images instead of the standard button images. However, the gray border from the standard buttons still remains, showing on the outside of my black button images.
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Creating a temporary directory in Windows?
What's the best way to get a temp directory name in Windows? I see that I can use GetTempPath and GetTempFileName to create a temporary file, but is there any equivalent to the Linux / BSD mkdtemp function for creating a temporary directory?
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