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class MyCacheBackendThing(Ellipsis):
    def get_or_set(self, key, timeout, setter):
        data = self.get(key, None)
        if data is None:
            data = setter
            if callable(data):
                data = data()
            self.set(key, data, timeout)
        return data

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# there must be a better way :|
current_view = resolve(request.path)
root_url = reverse('%s:index' % current_view.app_name)
index_view = resolve(root_url)

# getting the actual AdminSite instance.
# This works on Python 2.
adminsite = index_view.func.func_closure[0].cell_contents
# this works on Python 2 and 3, because Python 3 seems to lack
# func_closure, and Python 2/3 have different ordering for the 

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class Hi(object):
    def __repr__(self):
        return '<{cls.__module__}.{cls.__name__} ... other stuff!>'.format(cls=self.__class__)

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Python 2.7.5 (default, Jun 22 2013, 15:34:23)
>>> wtf = {'a', 2}
>>> wtf
set(['a', 2])

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class MyForm(Form):
    value = forms.ChoiceField(choices=())
    
    def __init__(self, *args, **kwargs):
        super(MyForm, self).__init__(*args, **kwargs)
        self.fields['value'].choices = get_choices(please_select='Please select:')

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from django.template.loaders import cached
from django.conf import settings

class Loader(cached.Loader):
    """ mostly cached loader """

    def load_template(self, template_name, template_dirs=None, exclusions=None):
                                                                                                                    
        if exclusions is None:
            exclusions = getattr(settings, 'MOSTLYCACHED_EXCLUDES', ())

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class MyForm(ModelForm):
    def __init__(self, *args, **kwargs):
        super(MyForm, self).__init__(*args, **kwargs)
        self.fields['myfield'].label = 'hello'
        
    class Meta:
        model = MyModel

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• If you type MyModel.<manager>.filter anywhere, you're doing it wrong.
  • Either create a Manager and do it there, or, better yet, use django-model-utils's PassThroughManager and write a proper, chainable queryset.
  • Possibly better than that would just be to have a queries module, which contains functions that return the correct querysets. Seriously, tracking down queries being made is much easier if there's only one place to look.
• If you're doing MyInstance.<related_name>.filter, I still hate you. Fix your manager/queryset or do that queries module I mentioned.
• If you want to do anything to a field on a Form, do it via self.fields[<fieldname>] in the __init__ method. Everything else is crap.
• If you're using a context processor and it touches the database, you'd better make it lazy() or I'll mow you down.
  • Seriously, otherwise it'll do queries for every RequestContext using view, even if it doesn't get used.
• Use django-pdb, django-debug-toolbar and `django-devs

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def runme():
    return 1

def dontrunme():
    return 2

a = {
    'key1': runme,
    'key2': runme,
    'key3': dontrunme,

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>>> from django.utils.functional import lazy
>>> lazy(lambda: None, None)()
Traceback (most recent call last):
  File "<console>", line 1, in <module>
  File "django/utils/functional.py", line 181, in __wrapper__
    return __proxy__(args, kw)
  File "django/utils/functional.py", line 83, in __init__
    self.__prepare_class__()
  File "django/utils/functional.py", line 95, in __prepare_class__
    for type_ in reversed(resultclass.mro()):