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Referring to the null object in Python
...
SyntaxError: cannot assign to keyword
It's therefore safe to assume that all None references are the same. There isn't any "custom" None.
To test for None use the is operator
When writing code you might be tempted to test for Noneness like this:
if value==None:
pass
Or to test for falsehood l...
Correct use of Multimapping in Dapper
...ID,
CustomerName.
This makes the spliton: parameter not so useful, especially when you're not sure what order the columns are returned in. Of course you could manually specify columns...but it's 2017 and we just rarely do that anymore for basic object gets.
What we do, and it's worked great fo...
how to change any data type into a string in python
...lso, alternatively try repr:
mystring = repr(myvariable) # '4'
This is called "conversion" in python, and is quite common.
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Stripping everything but alphanumeric chars from a string in Python
What is the best way to strip all non alphanumeric characters from a string, using Python?
11 Answers
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How do you calculate the average of a set of circular data? [closed]
... sum_i_from_1_to_N cos(a[i])
The method given by starblue is computationally equivalent, but his reasons are clearer and probably programmatically more efficient, and also work well in the zero case, so kudos to him.
The subject is now explored in more detail on Wikipedia, and with other uses, l...
How to override the [] operator in Python?
...rwise this will happen:
>>> myobj[5] = 1
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
AttributeError: MyClass instance has no attribute '__setitem__'
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How to get string objects instead of Unicode from JSON?
...unicode strings, then recurses through the entire decoded value to convert all strings to byte strings. This has a couple of undesirable effects:
A copy of the entire decoded structure gets created in memory
If your JSON object is really deeply nested (500 levels or more) then you'll hit Python's ...
Why does Razor _layout.cshtml have a leading underscore in file name?
...ith the underscore. And the Web Pages framework has been configured not to allow files with leading underscores in their names from being requested directly. Other .cshtml files within Web Pages generally need to be browsable. They are the equivalent of .asp or .php files.
The ASP.NET team have sta...
Difference between shared objects (.so), static libraries (.a), and DLL's (.so)?
... and shared objects are just different terms for the same thing - Windows calls them DLLs, while on UNIX systems they're shared objects, with the general term - dynamically linked library - covering both (even the function to open a .so on UNIX is called dlopen() after 'dynamic library').
They are ...
Access nested dictionary items via a list of keys?
...ist, value):
getFromDict(dataDict, mapList[:-1])[mapList[-1]] = value
All but the last element in mapList is needed to find the 'parent' dictionary to add the value to, then use the last element to set the value to the right key.
Demo:
>>> getFromDict(dataDict, ["a", "r"])
1
>>&g...