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super() fails with error: TypeError “argument 1 must be type, not classobj” when parent does not inh
I get some error that I can't figure out. Any clue what is wrong with my sample code?
4 Answers
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Getting MAC Address
...method under Linux I could find was to run ifconfig and run a regex across its output. I don't like using a package that only works on one OS, and parsing the output of another program doesn't seem very elegant not to mention error prone.
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Getting SyntaxError for print with keyword argument end=' '
... bar, end=" ")
or
print "foo" % bar, end=" "
i.e. as a call to print with a tuple as argument.
That's obviously bad syntax (literals don't take keyword arguments). In Python 3.x print is an actual function, so it takes keyword arguments, too.
The correct idiom in Python 2.x for end=" " is:
p...
How to create a DataTable in C# and how to add rows?
... "500";
dt.Rows.Add(_ravi);
To see the structure, or rather I'd rephrase it as schema, you can export it to an XML file by doing the following.
To export only the schema/structure, do:
dt.WriteXMLSchema("dtSchemaOrStructure.xml");
Additionally, you can also export your data:
dt.WriteXML("dtDa...
Cosine Similarity between 2 Number Lists
I need to calculate the cosine similarity between two lists , let's say for example list 1 which is dataSetI and list 2 which is dataSetII . I cannot use anything such as numpy or a statistics module. I must use common modules (math, etc) (and the least modules as possible, at that, to reduc...
How to calculate the bounding box for a given lat/lng location?
I have given a location defined by latitude and longitude.
Now i want to calculate a bounding box within e.g. 10 kilometers of that point.
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Does use of final keyword in Java improve the performance?
In Java we see lots of places where the final keyword can be used but its use is uncommon.
13 Answers
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Does Python support short-circuiting?
Does Python support short-circuiting in boolean expressions?
3 Answers
3
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Setting PayPal return URL and making it auto return?
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You have to enable auto return in your PayPal account, otherwise it will ignore the return field.
From the documentation (updated to reflect new layout Jan 2019):
Auto Return is turned off by default.
To turn on Auto Return:
Log in to your PayPal account at https://www.paypa...
Truncating all tables in a Postgres database
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FrustratedWithFormsDesigner is correct, PL/pgSQL can do this. Here's the script:
CREATE OR REPLACE FUNCTION truncate_tables(username IN VARCHAR) RETURNS void AS $$
DECLARE
statements CURSOR FOR
SELECT tablename FROM pg_tabl...