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Get Image size WITHOUT loading image into memory
...memory when calling .open. Looking at the docs of PIL 1.1.7, the docstring for .open says:
def open(fp, mode="r"):
"Open an image file, without loading the raster data"
There are a few file operations in the source like:
...
prefix = fp.read(16)
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fp.seek(0)
...
but these hardly con...
How do I check if a string is valid JSON in Python?
In Python, is there a way to check if a string is valid JSON before trying to parse it?
4 Answers
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Python ElementTree module: How to ignore the namespace of XML files to locate matching element when
...dle multiple namespaces and namespace aliases:
from io import StringIO # for Python 2 import from StringIO instead
import xml.etree.ElementTree as ET
# instead of ET.fromstring(xml)
it = ET.iterparse(StringIO(xml))
for _, el in it:
prefix, has_namespace, postfix = el.tag.partition('}')
if...
Understanding scala enumerations
...e Value.
It so happens that you can write val a, b, c = foo in Scala, and for each value a, b, and c the method foo will be called again and again. Enumeration uses this trick to increment an internal counter so that each value is individual.
If you open the Scala API docs for Enumeration and clic...
Django: Get list of model fields?
...herits from models.Model . I want to get a list of all the fields defined for this model. For example, phone_number = CharField(max_length=20) . Basically, I want to retrieve anything that inherits from the Field class.
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Which is better in python, del or delattr?
This may be silly, but it's been nagging the back of my brain for a while.
8 Answers
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What is the difference between exit and return? [duplicate]
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return returns from the current function; it's a language keyword like for or break.
exit() terminates the whole program, wherever you call it from. (After flushing stdio buffers and so on).
The only case when both do (nearly) the same thing is in the main() function, as a return from main per...
detach all packages while working in R
...names(sessionInfo()$otherPkgs)), detach, character.only=TRUE, unload=TRUE, force=TRUE))
One can attempt to unload base packages via $basePkgs and also attempt using unloadNamespace(loadedNamespaces()). However these typically are fraught with errors and could break basic functionality such as causi...
How do I count a JavaScript object's attributes? [duplicate]
...you get depends on the particular interpreter and what code has executed before yours. So, you somehow have to separate the ones you defined from those you got "for free."
Here's one way:
var foo = {"key1": "value1", "key2": "value2", "key3": "value3"};
Object.prototype.foobie = 'bletch'; // add p...
How to sort a list of objects based on an attribute of the objects?
... it's a list of Django objects, you should consider his solution. However, for the general case of sorting objects, my solution is probably best practice.
– Triptych
Dec 31 '08 at 17:12
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