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How to get the unique ID of an object which overrides hashCode()?

...iginal memory address for this object, but that's an implementation detail and you shouldn't rely on it. EDIT: Answer modified following Tom's comment below re. memory addresses and moving objects. share | ...
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Find object in list that has attribute equal to some value (that meets any condition)

... None) This gets the first item from the list that matches the condition, and returns None if no item matches. It's my preferred single-expression form. However, for x in test_list: if x.value == value: print("i found it!") break The naive loop-break version, is perfectly Pytho...
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Rails formatting date

... It's a time formatting function which provides you a way to present the string representation of the date. (http://ruby-doc.org/core-2.2.1/Time.html#method-i-strftime). From APIdock: %Y%m%d => 20071119 Calendar date (basic) %F => 2007-11-19 ...
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MongoDB atomic “findOrCreate”: findOne, insert if nonexistent, but do not update

as the title says, I want to perform a find (one) for a document, by _id, and if doesn't exist, have it created, then whether it was found or was created, have it returned in the callback. ...
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Python - Get path of root project structure

... packages; this is done to prevent directories with a common name, such as string, from unintentionally hiding valid modules that occur later on the module search path. In the simplest case, __init__.py can just be an empty file, but it can also execute initialization code for the package or set the...
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SQL Add foreign key to existing column

If I am using the following SQL command in SQL Server 2008 to update a table with a foreign key constraint: 6 Answers ...
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How do I compare version numbers in Python?

... version is. As distutils.version is undocumented, here's the relevant docstrings. share | improve this answer | follow | ...
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Downloading a file from spring controllers

...d = RequestMethod.GET) public void getFile( @PathVariable("file_name") String fileName, HttpServletResponse response) { try { // get your file as InputStream InputStream is = ...; // copy it to response's OutputStream org.apache.commons.io.IOUtils.copy(is, respon...
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How do I specify unique constraint for multiple columns in MySQL?

... For those people using MySQL workbench: go to the Indexes tab and select UNIQUE as your type. Give your index a name and check the appropriate columns under the section "Index Columns" – Pakman Jun 3 '13 at 20:42 ...
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How to delete object from array inside foreach loop?

I iterate through an array of objects and want to delete one of the objects based on it's 'id' property, but my code doesn't work. ...