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How can I add new keys to a dictionary?
...ted to strings). dict.update can also take another dictionary, but I personally prefer not to explicitly create a new dictionary in order to update another one.
– bgusach
Feb 13 '19 at 8:38
...
How do I override __getattr__ in Python without breaking the default behavior?
I want to override the __getattr__ method on a class to do something fancy but I don't want to break the default behavior.
...
Referencing system.management.automation.dll in Visual Studio
...g it updated, releasing new packages, etc.
– Ben Randall
Feb 5 '16 at 19:24
last updated 29/03/2013 " The owner has un...
In Python, how do I determine if an object is iterable?
...e a method like isiterable ? The only solution I have found so far is to call
21 Answers
...
Selecting multiple columns in a pandas dataframe
...).
df1 = df[['a', 'b']]
Alternatively, if it matters to index them numerically and not by their name (say your code should automatically do this without knowing the names of the first two columns) then you can do this instead:
df1 = df.iloc[:, 0:2] # Remember that Python does not slice inclusive of...
How can I access and process nested objects, arrays or JSON?
...as any string can be used as key in objects. The key-value pairs are also called the "properties".
Properties can be accessed either using dot notation
const value = obj.someProperty;
or bracket notation, if the property name would not be a valid JavaScript identifier name [spec], or the name is...
How to change field name in Django REST Framework
...get_alternate_name(self, obj):
return obj.alternate_name
Additionally, you can use serializers.CharField with source attribute:
class ParkSerializer(serializers.ModelSerializer):
location = serializers.CharField(source='other_fields')
class Meta:
model = Park
fiel...
Why do some C# lambda expressions compile to static methods?
...l implementation most likely varies slightly):
private class <Main>b__0
{
public int age;
public void withClosure(string s)
{
Console.WriteLine("My name is {0} and I am {1} years old", s, age)
}
}
private static class <Main>b__1
{
public static void withoutC...
Coding Practices which enable the compiler/optimizer to make a faster program
...act.
Expect to be disappointed and to have to work very hard indeed for small performance improvements. Modern compilers for mature languages such as Fortran and C are very, very good. If you read an account of a 'trick' to get better performance out of code, bear in mind that the compiler writer...
Is Big O(logn) log base e?
...nary search tree type of data structures, I see the Big O notation is typically noted as O(logn). With a lowercase 'l' in log, does this imply log base e (n) as described by the natural logarithm? Sorry for the simple question but I've always had trouble distinguishing between the different impli...