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How to fix “Attempted relative import in non-package” even with __init__.py
...ry to execute the above shell command, the fact that you need __init__.pys all the way down, and the __package__-modifying trickery (described below by BrenBarn) needed to allow these imports for executable scripts (e.g. when using a shebang and doing ./my_script.py at the Unix shell) would all be u...
How to import other Python files?
...
importlib was added to Python 3 to programmatically import a module.
It is just a wrapper around __import__, see the docs.
import importlib
moduleName = input('Enter module name:')
importlib.import_module(moduleName)
Note: the .py extension should be removed from mod...
Should all Python classes extend object?
...inheritance are different in ways that I won't even try to summarize here. All good documentation that I've seen about MI describes new-style classes.
Finally, old-style classes have disappeared in Python 3, and inheritance from object has become implicit. So, always prefer new style classes unless...
What is the JSF resource library for and how should it be used?
...
Actually, all of those examples on the web wherein the common content/file type like "js", "css", "img", etc is been used as library name are misleading.
Real world examples
To start, let's look at how existing JSF implementati...
What are the applications of binary trees?
...ningless - they are not a data structure, but a family of data structures, all with different performance characteristics. While it is true that unbalanced binary trees perform much worse than self-balancing binary trees for searching, there are many binary trees (such as binary tries) for which "b...
How do you query for “is not null” in Mongo?
...
This will return all documents with a key called "IMAGE URL", but they may still have a null value.
db.mycollection.find({"IMAGE URL":{$exists:true}});
This will return all documents with both a key called "IMAGE URL" and a non-null value.
d...
What do *args and **kwargs mean? [duplicate]
...r **kwargs as the last items in your function definition’s argument list allows that function to accept an arbitrary number of arguments and/or keyword arguments.
For example, if you wanted to write a function that returned the sum of all its arguments, no matter how many you supply, you could wr...
How do I get the full path to a Perl script that is executing?
...me of the script during execution. I discovered that depending on how you call the script $0 varies and sometimes contains the fullpath+filename and sometimes just filename . Because the working directory can vary as well I can't think of a way to reliably get the fullpath+filename of the scr...
Django select only rows with duplicate field values
... syntax is also how Django interprets you wanting to do a join. So, essentially when you try to filter on that, Django thinks you're trying to do a join with count which obviously doesn't exist. The fix is to specify a name for your annotation result, i.e. annotate(mycount=Count('id')) and then filt...
How to Update Multiple Array Elements in mongodb
...At this moment it is not possible to use the positional operator to update all items in an array. See JIRA http://jira.mongodb.org/browse/SERVER-1243
As a work around you can:
Update each item individually
(events.0.handled events.1.handled
...) or...
Read the document, do the edits
manually and ...