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super() raises “TypeError: must be type, not classobj” for new-style class
...e distinct. Here, OldStyle().__class__ is OldStyle, which does not inherit from object, while type(OldStyle()) is the instance type, which does inherit from object. Basically, an old-style class just creates objects of type instance (whereas a new-style class creates objects whose type is the class...
Is it possible to make abstract classes in Python?
...ending upon your Python version.
In Python 3.4 and above, you can inherit from ABC. In earlier versions of Python, you need to specify your class's metaclass as ABCMeta. Specifying the metaclass has different syntax in Python 3 and Python 2. The three possibilities are shown below:
# Python 3.4+
f...
What is InputStream & Output Stream? Why and when do we use them?
...screen shouldn't matter. All that matters is that you receive information from the stream (or send information into that stream.)
InputStream is used for many things that you read from.
OutputStream is used for many things that you write to.
Here's some sample code. It assumes the InputStream in...
Recover from git reset --hard?
Is there any way to recover uncommitted changes to the working directory from a git reset --hard HEAD ?
22 Answers
...
How to “pull” from a local branch into another one?
...that happened on master since I made it. This is all local. I want to pull from local master into local my_branch, but I can't do it. This doesn't seem to work, telling me that master isn't a git repository:
...
Python Sets vs Lists
...st(iterable):
... for i in iterable:
... pass
...
>>> from timeit import timeit
>>> timeit(
... "iter_test(iterable)",
... setup="from __main__ import iter_test; iterable = set(range(10000))",
... number=100000)
12.666952133178711
>>> timeit(
... ...
What is the iPad user agent?
From what I gather, the iPad is using iPhone OS, but with a different screen resolution from the iPhone and iPod touch. So many sites may have to change their user agent detection to adapt to the iPad.
...
URL Fragment and 302 redirects
...TP/1.1): Semantics and Content, has been published as a PROPOSED STANDARD. From the Changelog:
The syntax of the Location header field has been changed to allow all
URI references, including relative references and fragments, along
with some clarifications as to when use of fragments would n...
Calling Java from Python
What is the best way to call java from python?
(jython and RPC are not an option for me).
9 Answers
...
Why does Ruby have both private and protected methods?
... the defining class or its subclasses.
private methods can be called only from within the calling object. You cannot access another instance's private methods directly.
Here is a quick practical example:
def compare_to(x)
self.some_method <=> x.some_method
end
some_method cannot be priv...