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Get Image size WITHOUT loading image into memory

... This is a wrapper around libmagic which read as few bytes as possible in order to identify a file type signature. Relevant version of script: https://raw.githubusercontent.com/scardine/image_size/master/get_image_size.py [update] Hmmm, unfortunately, when applied to jpegs, the above gives "...
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What is getattr() exactly and how do I use it?

...mple you have an object person, that has several attributes: name, gender, etc. You access these attributes (be it methods or data objects) usually writing: person.name, person.gender, person.the_method(), etc. But what if you don't know the attribute's name at the time you write the program? For ...
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In Python, what happens when you import inside of a function? [duplicate]

... "appropriate scope" be module-level means each use of goo.this, goo.that, etc, is two dict lookups -- one for goo and one for the attribute name. Having it be "function level" pays one extra local-variable setting per run of the function (even faster than the dictionary lookup part!) but saves one...
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What is the basic difference between the Factory and Abstract Factory Design Patterns? [closed]

... pattern, you produce instances of implementations (Apple, Banana, Cherry, etc.) of a particular interface -- say, IFruit. With the Abstract Factory pattern, you provide a way for anyone to provide their own factory. This allows your warehouse to be either an IFruitFactory or an IJuiceFactory, with...
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Loading and parsing a JSON file with multiple JSON objects

... Highly active question. Earn 10 reputation in order to answer this question. The reputation requirement helps protect this question from spam and non-answer activity. ...
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Why do most C developers use define instead of const? [duplicate]

...== x, but if SCALE is an (extern) const, it will need to generate code to fetch the value and perform the multiplication because the value will not be known until the linking stage. (extern is needed to use the constant from several source files.) A closer equivalent to using #define is using enume...
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Can a local variable's memory be accessed outside its scope?

... be dead before the first method's local variables are dead. The relative order of the beginnings and endings of lifetimes of storages associated with local variables can be worked out ahead of time. For this reason, local variables are usually generated as storage on a "stack" data structure, bec...
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What is the difference between a field and a property?

...e can put logic in the Property also allows us to perform validation logic etc if we need it. C# 3 has the possibly confusing notion of autoproperties. This allows us to simply define the Property and the C#3 compiler will generate the private field for us. public class Person { private string _...
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what is the difference between a portlet and a servlet?

...ds they differ in containers, APIs, life cycle, configuration, deployment, etc. The main difference between portlet vs. servlet could be that while servlet always responds to single type of action - request, portlet (due to nature of its life cycle and stronger container bindings) has to respond t...
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(How) can I count the items in an enum?

...ainerClass *m_containers[Folders_MAX + 1]; .... m_containers[FA] = ...; // etc. Edit: Regarding { FA, FB, FC, Folders_MAX = FC} versus {FA, FB, FC, Folders_MAX]: I prefer setting the ...MAX value to the last legal value of the enum for a few reasons: The constant's name is technically more accur...