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Django ModelForm: What is save(commit=False) used for?
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As a "real example", consider a user model where the email address and the username are always the same, and then you could overwrite your ModelForm's save method like:
class UserForm(forms.ModelForm):
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def save(self):
# Sets username to email before saving
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How to change the name of a Django app?
...n see how I renamed an app, one commit at a time.
The example uses Python 2.7 and Django 1.8, but I'm confident the same process will work on at least Python 3.6 and Django 2.1.
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Using property() on classmethods
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SIGH double correction: this works in Python 2.7, but not Python 3.2.
– Michael Kelley
Dec 17 '11 at 4:14
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Bulk insert with SQLAlchemy ORM
...inserting rows, going from the most automated to the least.
With cPython 2.7, runtimes observed:
classics-MacBook-Pro:sqlalchemy classic$ python test.py
SQLAlchemy ORM: Total time for 100000 records 12.0471920967 secs
SQLAlchemy ORM pk given: Total time for 100000 records 7.06283402443 secs
SQLAl...
Determining 32 vs 64 bit in C++
..., but was curious to know if people could think of cases where this might fail or if there is a better way to do this. Please note we are trying to do this in a cross-platform, multiple compiler environment.
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How do I pass extra arguments to a Python decorator?
...913 25.3754 13.913C26.5612 13.913 27.4607 13.4902 28.1109 12.6616C28.1109 12.7229 28.1161 12.7799 28.121 12.8346C28.1256 12.8854 28.1301 12.9342 28.1301 12.983C28.1301 14.4373 27.2502 15.2321 25.777 15.2321C24.8349 15.2321 24.1352 14.9821 23.5661 14.7787C23.176 14.6393 22.8472 14.5218 22.5437 14.521...
Python strptime() and timezones?
...ng else. No mention of timezones.
Interestingly, [Win XP SP2, Python 2.6, 2.7] passing your example to time.strptime doesn't work but if you strip off the " %Z" and the " EST" it does work. Also using "UTC" or "GMT" instead of "EST" works. "PST" and "MEZ" don't work. Puzzling.
It's worth noting th...
How to merge dictionaries of dictionaries?
...tes for this to be legit Python (else they would be set literals in Python 2.7+) as well as append a missing brace:
dict1 = {1:{"a":'A'}, 2:{"b":'B'}}
dict2 = {2:{"c":'C'}, 3:{"d":'D'}}
and rec_merge(dict1, dict2) now returns:
{1: {'a': 'A'}, 2: {'c': 'C', 'b': 'B'}, 3: {'d': 'D'}}
Which match...
What is a “feature flag”?
...y longer, with a single check to see if the version number is greater than 2.7 or not; organizations that use them are typically including them as part of a comprehensive, system-wide product approach.
As others have mentioned, Facebook and LinkedIn pioneered this, but in 2018, a whole lot of organ...
Understanding repr( ) function in Python
... by object.__repr__). That was gradually toned down over the years, and by 2.7 and 3.x it's just true "for many types", and there are exceptions even in the stdlib (e.g,, a namedtuple type created as a local will give you a repr you can't eval), but it was the original idea.
– ...