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How to avoid circular imports in Python? [duplicate]
....py
Types of circular import problems
Circular import dependencies typically fall into two categories depending
on what you're trying to import and where you're using it inside each
module. (And whether you're using python 2 or 3).
1. Errors importing modules with circular imports
In some cases...
How to override the [] operator in Python?
...rwise this will happen:
>>> myobj[5] = 1
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
AttributeError: MyClass instance has no attribute '__setitem__'
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Extract traceback info from an exception object
...ion("foo occurred").with_traceback(tracebackobj)
These features are minimally described as part of the raise documentation.
All credit for this part of the answer should go to Vyctor, who first posted this information. I'm including it here only because this answer is stuck at the top, and Python...
Why dict.get(key) instead of dict[key]?
...
It allows you to provide a default value if the key is missing:
dictionary.get("bogus", default_value)
returns default_value (whatever you choose it to be), whereas
dictionary["bogus"]
would raise a KeyError.
If omitted...
Static files in Flask - robot.txt, sitemap.xml (mod_wsgi)
... achieved.)
it's not clean to add static files into the app root folder
finally, the proposed solution looks much cleaner than the adding middleware approach:
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Undocumented NSURLErrorDomain error codes (-1001, -1003 and -1004) using StoreKit
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All error codes are on "CFNetwork Errors Codes References" on the documentation (link)
A small extraction for CFURL and CFURLConnection Errors:
kCFURLErrorUnknown = -998,
kCFURLErrorCancelled = -999,
kCFURLErrorBadU...
JRE 1.7 - java version - returns: java/lang/NoClassDefFoundError: java/lang/Object
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This problem stems from an improper Java installation.
Possibility 1
NOTE: This scenario only applies to Java 8 and prior. Beginning with Java 9, the JRE is structured differently. rt.jar and friends no longer exist, and Pack200 is no longer used.
The Java standa...
Hidden Features of PHP? [closed]
...and getting a reference most of the time is great.
– Allain Lalonde
Sep 14 '08 at 17:46
1
This is...
Run certain code every n seconds [duplicate]
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This seems not to resolve the question at all... it does not repeat every second.
– Yan King Yin
Jul 5 '13 at 15:28
9
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Multiple Models in a single django ModelForm?
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But how? Usually a FormView only has a single form_class assigned to it.
– erikbwork
Oct 7 '16 at 17:42
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