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how to change any data type into a string in python
... you're writing your own class and you want str to work for you, add:
def __str__(self):
return "Some descriptive string"
print str(myObj) will call myObj.__str__().
repr is a similar method, which generally produces information on the class info. For most core library object, repr produces ...
How can I handle time zones in my webapp?
...s ambiguously used. This looks like a reference: en.wikipedia.org/wiki/Tz_database From what I can tell a "timezone" is "Area/Location", e.g. "America/New_York". That appears to be geographic which is great because for instance America/Los_Angeles means BOTH PST and PDT depending on whether the ...
What do I use for a max-heap implementation in Python?
...y heapq, and that there is no good alternative.
– ire_and_curses
Jun 10 '10 at 17:46
24
@gatoatig...
Difference between a theta join, equijoin and natural join
... yourself).
** I don't quite know what the result of SELECT * FROM table_expression; is. I know it is not a relation because, among other reasons, it can have columns with duplicate names or a column with no name. I know it is not a set because, among other reasons, the column order is significan...
Can a dictionary be passed to django models on create?
...our model is called MyModel:
# create instance of model
m = MyModel(**data_dict)
# don't forget to save to database!
m.save()
As for your second question, the dictionary has to be the final argument. Again, extra and extra2 should be fields in the model.
m2 =MyModel(extra='hello', extra2='world'...
Is gcc's __attribute__((packed)) / #pragma pack unsafe?
...
Yes, __attribute__((packed)) is potentially unsafe on some systems. The symptom probably won't show up on an x86, which just makes the problem more insidious; testing on x86 systems won't reveal the problem. (On the x86, misalig...
How do I avoid capturing self in blocks when implementing an API?
... If you're not using Automatic Reference Counting (ARC), you can do this:
__block MyDataProcessor *dp = self;
self.progressBlock = ^(CGFloat percentComplete) {
[dp.delegate myAPI:dp isProcessingWithProgress:percentComplete];
}
The __block keyword marks variables that can be modified inside th...
How to find the installed pandas version
...
Check pandas.__version__:
In [76]: import pandas as pd
In [77]: pd.__version__
Out[77]: '0.12.0-933-g281dc4e'
Pandas also provides a utility function, pd.show_versions(), which reports the version of its dependencies as well:
In [53]...
Creating a dynamic choice field
...passing the user to the form init
class waypointForm(forms.Form):
def __init__(self, user, *args, **kwargs):
super(waypointForm, self).__init__(*args, **kwargs)
self.fields['waypoints'] = forms.ChoiceField(
choices=[(o.id, str(o)) for o in Waypoint.objects.filter(use...
How do I get logs/details of ansible-playbook module executions?
...dd the following lines to your ansible configuration file:
[defaults]
log_path=/path/to/logfile
Ansible will look in several places for the config file:
ansible.cfg in the current directory where you ran ansible-playbook
~/.ansible.cfg
/etc/ansible/ansible.cfg
...