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Python unittest - opposite of assertRaises?
...the correct solution in fact. The solution proposed by user9876 is conceptually flawed: if you test for the non-raising of say ValueError, but ValueError is instead raised, your test must exit with a failure condition, not an error one. On the other hand, if in running the same code you would raise ...
What's the difference between eval, exec, and compile?
...
The short answer, or TL;DR
Basically, eval is used to evaluate a single dynamically generated Python expression, and exec is used to execute dynamically generated Python code only for its side effects.
eval and exec have these two differences:
eval accep...
Failed to install Python Cryptography package with PIP and setup.py
When I try to install the Cryptography package for Python through either pip install cryptography or by downloading the package from their site and running python setup.py , I get the following error:
...
How do I print to the debug output window in a Win32 app?
...you can use the L prefix:
OutputDebugStringW(L"My output string.");
Normally you will use the macro version together with the _T macro like this:
OutputDebugString(_T("My output string."));
If you project is configured to build for UNICODE it will expand into:
OutputDebugStringW(L"My output s...
When is “i += x” different from “i = i + x” in Python?
...
This depends entirely on the object i.
+= calls the __iadd__ method (if it exists -- falling back on __add__ if it doesn't exist) whereas + calls the __add__ method1 or the __radd__ method in a few cases2.
From an API perspective, __iadd__ is supposed to be used fo...
Understanding __get__ and __set__ and Python descriptors
...th the Temperature class). For example:
temp=Temperature()
temp.celsius #calls celsius.__get__
Accessing the property you assigned the descriptor to (celsius in the above example) calls the appropriate descriptor method.
instance in __get__ is the instance of the class (so above, __get__ would r...
android studio 0.4.2: Gradle project sync failed error
...e folder in the user home directory
Restart Android Studio let it download all the Gradle stuff it needs
Gradle build success !
Rebuild project.... success !
Out of curiousity I compared the structure of the old .gradle and the new one... they were pretty different !
So I'll see how 0.4.2 goes :...
Is arr.__len__() the preferred way to get the length of an array in Python?
...ples:
my_tuple = (1,2,3,4,5)
len(my_tuple)
# 5
And strings, which are really just arrays of characters:
my_string = 'hello world'
len(my_string)
# 11
It was intentionally done this way so that lists, tuples and other container types or iterables didn't all need to explicitly implement a public...
Selenium: FirefoxProfile exception Can't load the profile
...
Update:
Selenium team fixed in latest version. For almost all environments the fix is:
pip install -U selenium
Unclear at which version it was fixed (apparently r13122), but certainly by 2.26.0 (current at time of update) it is fixed.
This error means that _wait_until_conn...
How can I apply a function to every row/column of a matrix in MATLAB?
...umns if there's only one row, or higher dimensions if the lower dimensions all have size==1). However, bsxfun works for any function, including (and especially) user-defined functions.
For example, let's say you have a matrix A and a row vector B. E.g., let's say:
A = [1 2 3;
4 5 6;
7 8 ...