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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 ./...
How do you get a query string on Flask?
... as with a dict and .get, you'd just get None.
– JPEG_
Oct 23 '16 at 8:46
5
@LyndsySimon: Well sp...
Behaviour of increment and decrement operators in Python
...so far as they don't explain what happens.
To be exact, +x evaluates to x.__pos__() and ++x to x.__pos__().__pos__().
I could imagine a VERY weird class structure (Children, don't do this at home!) like this:
class ValueKeeper(object):
def __init__(self, value): self.value = value
def __s...
How do I reference an existing branch from an issue in GitHub?
...ant to do this, I manually make the link like this:
[a link to a branch](/_user_/_project_/tree/_branch_)
Where _user_, _project_, and _branch_ should be replaced with the parts of the branch's URL. For example, a branch in GitHub's "linguist" project:
[api-changes branch in github/linguist](/g...
What is function overloading and overriding in php?
...that method.
In PHP, you can only overload methods using the magic method __call.
An example of overriding:
<?php
class Foo {
function myFoo() {
return "Foo";
}
}
class Bar extends Foo {
function myFoo() {
return "Bar";
}
}
$foo = new Foo;
$bar = new Bar;
echo($foo-&...
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}") ...
How do I pass a method as a parameter in Python
...thodToRun()
return result
obj.method2(obj.method1)
Note: I believe a __call__() method does exist, i.e. you could technically do methodToRun.__call__(), but you probably should never do so explicitly. __call__() is meant to be implemented, not to be invoked from your own code.
If you wanted me...
detach all packages while working in R
...h()[pos]’. This can
be an unquoted name or a character string but _not_ a
character vector. If a number is supplied this is taken as
‘pos’.
So we need to repeatedly call detach() once per element of pkg. There are a couple of other arguments we need to specify to get thi...
ElasticSearch: Unassigned Shards, how to fix?
...enable shard allocation.
# v0.90.x and earlier
curl -XPUT 'localhost:9200/_settings' -d '{
"index.routing.allocation.disable_allocation": false
}'
# v1.0+
curl -XPUT 'localhost:9200/_cluster/settings' -d '{
"transient" : {
"cluster.routing.allocation.enable" : "all"
}
}'
Elas...
Hash function that produces short hashes?
...ike the accepted answer):
import base64
import hashlib
import uuid
unique_id = uuid.uuid4()
# unique_id = UUID('8da617a7-0bd6-4cce-ae49-5d31f2a5a35f')
hash = hashlib.sha1(str(unique_id).encode("UTF-8"))
# hash.hexdigest() = '882efb0f24a03938e5898aa6b69df2038a2c3f0e'
result = base64.b64encode(has...