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Django: How to completely uninstall a Django app?
...clear docs for more information. Basically, running ./manage.py sqlclear my_app_name gets you get the SQL statements that should be executed to get rid of all traces of the app in your DB. You still need to copy and paste (or pipe) those statements into your SQL client. For Django 1.7 and up, use ./...
What is the difference between sigaction and signal?
...turns.
The signal() function (usually) resets the signal action back to SIG_DFL (default) for almost all signals. This means that the signal() handler must reinstall itself as its first action. It also opens up a window of vulnerability between the time when the signal is detected and the handler ...
TypeError: 'NoneType' object is not iterable in Python
...r a variable containing None. The operation was performed by invoking the __iter__ method on the None.
None has no __iter__ method defined, so Python's virtual machine tells you what it sees: that NoneType has no __iter__ method.
This is why Python's duck-typing ideology is considered bad. The...
Remove duplicate dict in list in Python
... {'a': 3222, 'b': 1234},
{'a': 123, 'b': 1234}]
seen = set()
new_l = []
for d in l:
t = tuple(d.items())
if t not in seen:
seen.add(t)
new_l.append(d)
print new_l
Example output:
[{'a': 123, 'b': 1234}, {'a': 3222, 'b': 1234}]
Note: As pointed out by @alexis ...
Objective-C Static Class Level variables
...ing a Class Object in Apple's Objective-C docs.
– big_m
Oct 3 '11 at 16:02
...
How do I check if a string is valid JSON in Python?
...on script returns a boolean if a string is valid json:
import json
def is_json(myjson):
try:
json_object = json.loads(myjson)
except ValueError as e:
return False
return True
Which prints:
print is_json("{}") #prints True
print is_json("{asdf}") ...
Disable individual Python unit tests temporarily
...he unittest.skip decorator.
@unittest.skip("reason for skipping")
def test_foo():
print('This is foo test case.')
@unittest.skip # no reason needed
def test_bar():
print('This is bar test case.')
For other options, see the docs for Skipping tests and expected failures.
...
How do you round to 1 decimal place in Javascript?
...)
You might want to create a function for this:
function roundedToFixed(_float, _digits){
var rounded = Math.pow(10, _digits);
return (Math.round(_float * rounded) / rounded).toFixed(_digits);
}
share
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...
Why does 'continue' behave like 'break' in a Foreach-Object?
..., it simulates the continue in a loop.
1..100 | ForEach-Object {
if ($_ % 7 -ne 0 ) { return }
Write-Host "$($_) is a multiple of 7"
}
There is a gotcha to be kept in mind when refactoring. Sometimes one wants to convert a foreach statement block into a pipeline with a ForEach-Object cmdl...
How to make a python, command-line program autocomplete arbitrary things NOT interpreter
... return options[state]
else:
return None
readline.parse_and_bind("tab: complete")
readline.set_completer(completer)
The official module docs aren't much more detailed, see the readline docs for more info.
...