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What is the “__v” field in Mongoose

... now, but I wanted something that I could put in the Schema directly so in all queries. – diosney Mar 24 '14 at 11:52 ...
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How to parse/read a YAML file into a Python object? [duplicate]

...ame: Node 2 branch2-1: name: Node 2-1 And you've installed PyYAML like this: pip install PyYAML And the Python code looks like this: import yaml with open('tree.yaml') as f: # use safe_load instead load dataMap = yaml.safe_load(f) The variable dataMap now contains...
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Android: upgrading DB version and adding new table

... 1. About onCreate() and onUpgrade() onCreate(..) is called whenever the app is freshly installed. onUpgrade is called whenever the app is upgraded and launched and the database version is not the same. 2. Incrementing the db version You need a constructor like: MyOpenHelp...
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How do I expire a PHP session after 30 minutes?

...ms with filesystems where atime tracking is not available. So it additionally might occur that a session data file is deleted while the session itself is still considered as valid because the session data was not updated recently. And second: session.cookie_lifetime session.cookie_lifetime ...
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How to change plot background color?

...he stateful API (if you're doing anything more than a few lines, and especially if you have multiple plots, the object-oriented methods above make life easier because you can refer to specific figures, plot on certain axes, and customize either) plt.plot(...) ax = plt.gca() Then you can use set_...
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How to check a checkbox in capybara?

... I couldn't find a way to make this work with the CSS selector at all! There must be some way to escape the square bracket but I couldn't find it. I had to resort to an XPath finder: find(:xpath, ".//input[@id='Extrapainful[]'][@value='12345']").set(true) – Jon M ...
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Syntax Error: Not a Chance

...ng blocks by braces instead of indentation will never be implemented. Normally, imports from the special __future__ module enable features that are backwards-incompatible, such as the print() function, or true division. So the line from __future__ import braces is taken to mean you want to enable ...
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Best algorithm for detecting cycles in a directed graph [closed]

What is the most efficient algorithm for detecting all cycles within a directed graph? 14 Answers ...
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Check if OneToOneField is None in Django

... Thank you for this solution. Unfortunately, this doesn't work all the time. In case you want to work with select_related() now or in the future -- or maybe even to be sure you also handle other sorts of magic which may happen elsewhere -- you have to extend the test as follows: if hasat...
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Constructors vs Factory Methods [closed]

...nd highly significant results indicating that factories are detrimental to API usability: "users require significantly more time (p=0.005) to construct an object with a factory than with a constructor" [The Factory Pattern in API Design: A Usability Evaluation]. – mdeff ...