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Django set default form values
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@Phlip: Don't override View.get_form to set initial data. Any CBV with a FormMixin (basically all CBVs that create or edit data) can either use a class-level initial variable (for unchanging defaults) or you can override FormMixin.get_initial() to return ...
Days between two dates? [duplicate]
...est for calendar checks.
from datetime import timedelta, datetime
def cal_days_diff(a,b):
A = a.replace(hour = 0, minute = 0, second = 0, microsecond = 0)
B = b.replace(hour = 0, minute = 0, second = 0, microsecond = 0)
return (A - B).days
if __name__ == '__main__':
x = datetime...
What do *args and **kwargs mean? [duplicate]
...ments, no matter how many you supply, you could write it like this:
def my_sum(*args):
return sum(args)
It’s probably more commonly used in object-oriented programming, when you’re overriding a function, and want to call the original function with whatever arguments the user passes in.
Y...
Is there a foreach loop in Go?
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https://golang.org/ref/spec#For_range
A "for" statement with a "range" clause iterates through all entries
of an array, slice, string or map, or values received on a channel.
For each entry it assigns iteration values to corresponding iteration
v...
What does `:_*` (colon underscore star) do in Scala?
...to the method with repeated parameters (as denoted with Node* above).
The _* type annotation is covered in "4.6.2 Repeated Parameters" of the SLS.
The last value parameter of a parameter section may be suffixed by “*”, e.g. (..., x:T *). The type of such a repeated parameter inside th...
Python: How do I make a subclass from a superclass?
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# Initialize using Parent
#
class MySubClass(MySuperClass):
def __init__(self):
MySuperClass.__init__(self)
Or, even better, the use of Python's built-in function, super() (see the Python 2/Python 3 documentation for it) may be a slightly better method of calling the parent for ...
using lodash .groupBy. how to add your own keys for grouped output?
...ame": "eddie",
"color": "green",
"age": "77"
}];
console.log(
_.chain(data)
// Group the elements of Array based on `color` property
.groupBy("color")
// `key` is group's name (color), `value` is the array of objects
.map((value, key) => ({ color: key, users: valu...
Iterating through a JSON object
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Your loading of the JSON data is a little fragile. Instead of:
json_raw= raw.readlines()
json_object = json.loads(json_raw[0])
you should really just do:
json_object = json.load(raw)
You shouldn't think of what you get as a "JSON object". What you have is a list. The list contains two d...
In Intellij, how do I toggle between camel case and underscore spaced?
...storyOfPresentIllness and when i write the sql, I want to name it history_of_present_illness . Is there a keyboard shortcut to switch from one to the other when I have the phrase highlighted? Or perhaps a plugin that can do this?
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Python string class like StringBuilder in C#?
...st of length-one strings. (To make this from a string, you'd call list(your_string). You could also use a UserString.MutableString for this.
(c)StringIO.StringIO is useful for things that would otherwise take a file, but less so for general string building.
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