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Extract substring in Bash
...o-based) and "5" is the length. Also, +1 for @gontard 's link that lays it all out!
– Doktor J
Sep 12 '14 at 17:32
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Unique BooleanField value in Django?
... save method of the model and if you've set the boolean to True, make sure all others are set to False.
from django.db import transaction
class Character(models.Model):
name = models.CharField(max_length=255)
is_the_chosen_one = models.BooleanField()
def save(self, *args, **kwargs):
...
How to validate an e-mail address in swift?
...s quite funny that ............ as well as (1) the regex being utterly, totally incorrect (2) the regex (even within the context of what it's trying to do) has major errors (3) the Swift is wrong (4) even setting that aside, the style is totally wrong (5) not that it matters given all the rest but i...
How to know if an object has an attribute in Python
...n is that, if the property is likely to be there most of the time, simply call it and either let the exception propagate, or trap it with a try/except block. This will likely be faster than hasattr. If the property is likely to not be there most of the time, or you're not sure, using hasattr will pr...
Change the maximum upload file size
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On Linux, it's usually in /etc/php/ or something along those lines. If you're on a shared server, you're out of luck unless your hosting provider is generous enough to provide a per-user php.ini file.
– Johannes Gorset
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How to check if the user can go back in browser history or not
...ple, be allowed to figure out what bank I use, which school my kids go to, etc... Therefore, the browsers won't allow access to that property
– McAden
Mar 16 at 15:12
add a co...
Python: Is it bad form to raise exceptions within __init__?
...t have been designed with exception safety in mind, the destructor is not called if an exception is thrown in the constructor of an object (meaning that the initialization of the object is incomplete). This is often not the case in scripting languages, such as Python. For example, the following code...
How to make a valid Windows filename from an arbitrary string?
...: Bar" that I want to use as a filename, but on Windows the ":" char isn't allowed in a filename.
14 Answers
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Delete column from pandas DataFrame
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This answer isn't really correct - the pandas developers didn't, but that doesn't mean it is hard to do.
– wizzwizz4
Sep 30 '17 at 9:42
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Loop backwards using indices in Python?
... This is better than the accepted answer since it doesn't actually allocate all the numbers in memory (in Python 3 the accepted answer wouldn't either), plus it's more obvious what is happening.
– Blixt
Mar 23 '12 at 13:52
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