Python One-Liners You Should KnowJan 08, 2020 • 5 minutes • 2509 views
Python is known for its simplicity. At the same time, it’s fascinating to see how powerful one line of Python code can be sometimes. This article features 5 such one-liners that can do awesome things, or at least save you a few minutes.
Python has a built-in module for formatting JSON files. Suppose you want to format the JSON file at this link.
Open Terminal, and run this command:
curl "https://www.metaweather.com/api/location/search/?lattlong=36.96,-122.02" | python -m json.tool
You can combine
python -m json.tool with any UNIX command using the pipeline
|. For example, to read and format a locally saved JSON file, you can run use it with the cat command:
cat file.json | python -m json.tool
The output of command before the pipeline
| is sent to the command following it.
We know that Python 3 has the
print() function. The complete function looks like this:
print(*objects , sep=' ' , end='\n' , file=sys.stdout , flush=False)
You can change the default value of the
file parameter to save the output as a file on the disk.
print("Hello, World!", file=open('file.txt', 'w'))
This is a quite handy way of writing (or appending) output to a file.
Hide User Input
A lot of the times you need to prompt the user for a confidential input (like keys or passwords). The
input() would expose as the user types in a key.
Fortunately, you can use the
getpass module (preinstalled) to hide user input.
import getpass pwd = getpass.getpass("ENTER PASSWORD:" )
Use the Dictionary
No, I don’t mean a Python dictionary object. Literally the dictionary, the one that is used by your operating system as an English dictionary. Actually your system has this file called
words.txt which contains around 235,000+ English words.
You can have a look at this file at
usr/share/dict/words.txt in most of the UNIX based systems, or simply click here to open it in your browser.
This file can be used in a lot of ways — spotting misspellings in a large word document or simply verifying if an input entered by the user is a valid English word.
Let us check if “python” is a valid English word:
if "python".casefold() in open('/usr/share/dict/words/').read(): print("EXISTS")
macOS and many other UNIX based operating systems ship with this
words.txt file. But if you don’t find this file in your system, you can install it with this command:
apt-get install --reinstall wamerican
Start a Local Server
This is perhaps the quickest way to start a local webserver. Just go the directory where you have saved your website and run this command:
python -m http.server 8000
Of course, you can run multiple local servers with this command as long they have different port numbers.
Python is great when it comes to doing more and writing less. If you are interested in more Python one-liners, do check out: Powerful Python One-Liners
Hope you enjoyed reading this article.
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