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Calculate difference in keys contained in two Python dictionaries
...s:
diff = set(dictb.keys()) - set(dicta.keys())
Here is a class to find all the possibilities: what was added, what was removed, which key-value pairs are the same, and which key-value pairs are changed.
class DictDiffer(object):
"""
Calculate the difference between two dictionaries as:
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Python nested functions variable scoping [duplicate]
I've read almost all the other questions about the topic, but my code still doesn't work.
10 Answers
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How to export all collections in MongoDB?
I want to export all collections in MongoDB by the command:
26 Answers
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What is the use of the %n format specifier in C?
...reak up or modify the resulting string, since the value stored is an array index into the resulting string. This application is a lot more useful, however, with sscanf, especially since functions in the scanf family don't return the number of chars processed but the number of fields.
Another really...
Undefined symbols for architecture i386: _OBJC_CLASS_$_SKPSMTPMessage", referenced from: error
...r the "Compile Sources" step of the "Build Phases" tab of your target. Normally Xcode does this for you, but sometimes it loses the plot and you need to add the .m file manually.
To do this:
TargetSettings -> Build Phases -> Compile Sources -> add your .m class ->Build and Run
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What's the difference between a Python “property” and “attribute”?
I am generally confused about the difference between a "property" and an "attribute", and can't find a great resource to concisely detail the differences.
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Is having an 'OR' in an INNER JOIN condition a bad idea?
...e WHERE parentId = 1 OR id = 2 will use a concatenation if both fields are indexed so theoretically there is nothing that would prevent doing the same thing in a loop. Whether SQL Server will build this plan actually or not, depends on very many factors, but I've never seen it built in real life.
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What does the regular expression /_/g mean?
...egex matches the _ character.
The g means Global, and causes the replace call to replace all matches, not just the first one.
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How to validate an email address in JavaScript
...b"@gmail.com, _@gmail.com, 1@gmail.com , 1_example@something.gmail.com are all valid, but Gmail will never allow any of these email addresses. You should do this by accepting the email address and sending an email message to that email address, with a code/link the user must visit to confirm validit...
Is there a command to refresh environment variables from the command prompt in Windows?
... environment variables with a vbs script, but you need a bat script to actually change the current environment variables, so this is a combined solution.
Create a file named resetvars.vbs containing this code, and save it on the path:
Set oShell = WScript.CreateObject("WScript.Shell")
filename =...