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import module from string variable

... Finally, also remember that you can't import anything if there is no __init__.py in the folder with file you are trying to import. – Seanny123 Dec 6 '13 at 7:31 ...
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Is there a difference between “==” and “is”?

... a True In your case, the second test only works because Python caches small integer objects, which is an implementation detail. For larger integers, this does not work: >>> 1000 is 10**3 False >>> 1000 == 10**3 True The same holds true for string literals: >>> "a" i...
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Union of dict objects in Python [duplicate]

...yptic, and it immediately makes most readers balk and the remainder assume all the keys in x would have to be legal parameter names. IMHO, the fact it works is a bug in the name-checking mechanisms in the implementation. What happens when you rely on bugs? They either get fixed, or become politic...
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What is the best regular expression to check if a string is a valid URL?

... I wrote my URL (actually IRI, internationalized) pattern to comply with RFC 3987 (http://www.faqs.org/rfcs/rfc3987.html). These are in PCRE syntax. For absolute IRIs (internationalized): /^[a-z](?:[-a-z0-9\+\.])*:(?:\/\/(?:(?:%[0-9a-f][0-9a-f]...
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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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Rolling median algorithm in C

...milar too in a standalone C++ class / C subroutine. Note that this are actually two implementations in one, see src/library/stats/man/runmed.Rd (the source of the help file) which says \details{ Apart from the end values, the result \code{y = runmed(x, k)} simply has \code{y[j] = median(x[(j-k2...
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What is the _snowman param in Ruby on Rails 3 forms for?

...net Explorer (5, 6, 7 and 8) to encode its parameters as unicode. Specifically, this bug can be triggered if the user switches the browser's encoding to Latin-1. To understand why a user would decide to do something seemingly so crazy, check out this google search. Once the user has put the web-sit...
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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 do I get an object's unqualified (short) class name?

... You can do this with reflection. Specifically, you can use the ReflectionClass::getShortName method, which gets the name of the class without its namespace. First, you need to build a ReflectionClass instance, and then call the getShortName method of that instance:...
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Regex lookahead, lookbehind and atomic groups

...ely follow, and stop as backtracking is disabled A non-atomic group will allow backtracking; if subsequent matching ahead fails, it will backtrack and use alternative patterns until a match for the entire expression is found or all possibilities are exhausted. (foo|foot)s applied to foots will: ...