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Counting the number of True Booleans in a Python List
...th the constant True, a simple sum is fine. However, keep in mind that in Python other values evaluate as True as well. A more robust solution would be to use the bool builtin:
>>> l = [1, 2, True, False]
>>> sum(bool(x) for x in l)
3
UPDATE: Here's another similarly robust so...
What to do with “Unexpected indent” in python?
How do I rectify the error "unexpected indent" in python?
16 Answers
16
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How to install psycopg2 with “pip” on Python?
...hes.
Option 1
Install the psycopg2-binary PyPI package instead, it has Python wheels for Linux and Mac OS.
pip install psycopg2-binary
Option 2
Install the prerequsisites for building the psycopg2 package from source:
Debian/Ubuntu
Python 3
sudo apt install libpq-dev python3-dev
You m...
Best practice for Python assert
...g them. This is more an example of properties in and of themselves: docs.python.org/library/functions.html#property
– Jason Baker
Jun 3 '09 at 13:43
3
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Why does multiprocessing use only a single core after I import numpy?
...e, but I thought I would ask here in case anyone has some insight from the Python end of things.
3 Answers
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Chain-calling parent initialisers in python [duplicate]
...
The way you are doing it is indeed the recommended one (for Python 2.x).
The issue of whether the class is passed explicitly to super is a matter of style rather than functionality. Passing the class to super fits in with Python's philosophy of "explicit is better than implicit".
...
How do I initialize the base (super) class?
In Python, consider I have the following code:
4 Answers
4
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Pythonic way to add datetime.date and datetime.time objects
...
It's in the python docs.
import datetime
datetime.datetime.combine(datetime.date(2011, 1, 1),
datetime.time(10, 23))
returns
datetime.datetime(2011, 1, 1, 10, 23)
...
Format numbers to strings in Python
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Starting with Python 3.6, formatting in Python can be done using formatted string literals or f-strings:
hours, minutes, seconds = 6, 56, 33
f'{hours:02}:{minutes:02}:{seconds:02} {"pm" if hours > 12 else "am"}'
or the str.format fun...
What 'additional configuration' is necessary to reference a .NET 2.0 mixed mode assembly in a .NET 4
...d mode assembly, you need to modify your App.Config file to include:
<?xml version="1.0"?><configuration> <startup useLegacyV2RuntimeActivationPolicy="true"> <supportedRuntime version="v4.0" sku=".NETFramework,Version=v4.0"/> </startup></configuration>
The ...