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Does reading an entire file leave the file handle open?
...hat on the particular Python implementation.
To understand what this is all about, pay particular attention to the actual file object. In your code, that object is mentioned only once, in an expression, and becomes inaccessible immediately after the read() call returns.
This means that the file...
Why is Python 3.x's super() magic?
In Python 3.x, super() can be called without arguments:
1 Answer
1
...
How do I execute a string containing Python code in Python?
...;>> x
4
However, the first step should be to ask yourself if you really need to. Executing code should generally be the position of last resort: It's slow, ugly and dangerous if it can contain user-entered code. You should always look at alternatives first, such as higher order functions, ...
How do I use raw_input in Python 3
...
There was originally a function input() which acted something like the current eval(input()). It was a leftover from when Python was less security conscious. The change simplified the language. See also "import this" for a deeper explanat...
Immutability of Strings in Java
...t, and changing a reference. s2 still points to the same object as we initially set s1 to point to. Setting s1 to "Help!" only changes the reference, while the String object it originally referred to remains unchanged.
If strings were mutable, we could do something like this:
String s1 = "Hello";
St...
Rename Files and Directories (Add Prefix)
I would like to add prefix on all folders and directories.
10 Answers
10
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How to check a string for specific characters?
...r other characters.
... or
pattern = re.compile(r'\d\$,')
if pattern.findall(s):
print('Found')
else
print('Not found')
... or
chars = set('0123456789$,')
if any((c in chars) for c in s):
print('Found')
else:
print('Not Found')
[Edit: added the '$' in s answers]
...
What is a clean, pythonic way to have multiple constructors in Python?
...
Actually None is much better for "magic" values:
class Cheese():
def __init__(self, num_holes = None):
if num_holes is None:
...
Now if you want complete freedom of adding more parameters:
class Cheese...
AngularJS HTTP post to PHP and undefined
...send that as data. Make sure that this query string is URL encoded. If manually built (as opposed to using something like jQuery.serialize()), Javascript's encodeURIComponent() should do the trick for you.
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How to change the name of a Django app?
...e changed the name of an app in Django by renaming its folder, imports and all its references (templates/indexes). But now I get this error when I try to run python manage.py runserver
...