Tips to write pythonic

2 min readFeb 2, 2020

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Python community has a special words for talking about code that follows the best practices for writing in python, pythonic. The following are some tips to make the most of Python programming language.

I recommend as reference the PEP-8 (Python Enhancement Proposal) document which provides guidelines and best practices on how to write Python code. It enables to achieve better readability and consistency throughout code.

This is a short and straight to the point article, listing some good practices.

Naming

Do not use l(small L), 0(capital o) or I (capital i)for variable names, as these can be mistaken for 1 (one) and 0(zero). Seeing O = 2 gives a strange feeling…
Choose explicit names. learning_rate is better than lr

|  Topic   | Good examples           | Bad examples     |
|----------+-------------------------+------------------|
| Function | function, my_function   | MyFunction, func |
| Variable | x, var, my_variable     | Var, Myvar       |
| Class    | Model, MyClass          | model, my_class  |
| Method   | class_method, method    |                  |
| Constant | CONSTANT, MY_CONSTANT   | myconstant       |
| Module   | module.py, my_module.py | my-module.py     |
| Package  | package, mypackage      |                  |

Blank lines

Blank lines help readability

class MIDIScore:
    def my_method(self):
        passdef my_other_method(self):
        passclass Pianoroll:
    pass

Line breaking

Use maximum line length of 79
Break lines if necessary, with ( ), \

total = (first_variable
        + second_variable
        - third_variable)from mypkg import example1, \
                  example2, example3

Indentation

Use it to improve readability

def train(model, weights, data,
          epochs, batch_size):
    model.load_weights(weights)
    model.fit(data, epochs, batch_size)

Use built-in libraries

Instead of reinventing the wheel, most common processing can be done using built-in features of python default libraries. Python3 has significantly improved these libraries, when it comes to argument parsing, path processing, etc.

Handling command-line arguments with argparse
Logging info, error or warning messages with logging
To handle paths, use pathlib

Miscellaneous implementations

You can use startwith and endwith methods for str objects.

# Not recommended :(
if word[:3] == 'cat':
    print('The word starts with "cat"')# Recommended :)
if word.startswith('cat'):
    print('The word starts with "cat"')

PEP 8 — Style Guide for Python code

Fluent Python, by Luciano Ramalho

See this article on my website