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Difference between os.getenv and os.environ.get
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One difference observed (Python27):
os.environ raises an exception if the environmental variable does not exist.
os.getenv does not raise an exception, but returns None
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npm failed to install time with make not found error
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edited Jan 2 '18 at 23:39
Bob Fanger
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Stop setInterval
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You need to set the return value of setInterval to a variable within the scope of the click ha...
How do I create a dictionary with keys from a list and values defaulting to (say) zero? [duplicate]
I have a = [1,2,3,4] and I want d = {1:0, 2:0, 3:0, 4:0}
5 Answers
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Find which version of package is installed with pip
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As of pip 1.3, there is a pip show command.
$ pip show Jinja2
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Name: Jinja2
Version: 2.7.3
Location: /path/to/virtualenv/lib/python2.7/site-packages
Requires: markupsafe
In older versions, pip freeze and grep should do the job nicely.
$ pip freeze | grep Jinja2
Jinja2==2.7.3
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How do I use Node.js Crypto to create a HMAC-SHA1 hash?
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edited Dec 2 '19 at 17:31
answered Sep 20 '11 at 4:38
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How do I provide JVM arguments to VisualVM?
I'm using VisualVM from JDK 1.6.0_26 to profile a Java webapp running under Tomcat, but VisualVM often tells me that it doesn't have enough memory to take a snapshot, and to use the -Xmx switch to provide more memory to Netbeans. The problem is, I'm running VisualVM outside of Netbeans, so how can I...
Check if a table exists in Rails
...ake task that won't work unless a table exists. I'm working with more than 20 engineers on a website so I want to make sure they have migrated the table before they can do a rake task which will populate that respective table.
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Move an item inside a list?
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answered Jul 3 '10 at 23:15
David ZDavid Z
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