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Rahul Banerjee
Rahul Banerjee

Posted on • Originally published at realpythonproject.com

#Day20 - Naming Conventions in Python

Today we will discuss some Naming conventions in Python.

Different type of naming conventions

We will name the same variable in the different conventions. Let's assume, we are trying to name a list or array which stores the marks of students.

Snake Case

students_marks
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The words are separated using an underscore. Each word starts with a lower case letter.

Pascal Case

StudentMarks
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Each word starts with an upper case. They are not separated using any separator.

Camel Case

studentMarks
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The first word starts with a lower case letter and the following words start with an upper case letter.

Kebab Case

student-marks
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Each word starts with a lower case and they are separated with hyphens.

Hungarian Notation

arrStudentMarks
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In this variable naming convention, we add the data structure at the beginning of the name.

Naming convention in Python

Packages

Use snake_case for naming packages

import streamlit
import pulp
import flask_sqlalchemy
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Modules

Modules are the functions you import from a package. They also use snake_case

from streamlit import subheader, text, markdown, title
from datetime import datetime
from flask import jsonify
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Classes

Classes should be named in "CamelCase" format.

class MyClass:
    def __init__():
        pass

class Dog:
    def __init__():
        pass
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Below is another example of importing classes from a Module

from flask import Flask
from flask_sqlalchemy import SQLAlchemy
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Global (module-level) Variables

Global variables should follow snake_case

variable = 1
variable_one = 2

def func():
      global variable
      global variable_one
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Methods

  • Public method should be named using snake_case
  • By convention, private methods should be starting with an underscore ('_')
class MyClass:
    '''
    This is a public method
    '''
    def  public_method():
        pass

    '''
    This is a private method
    '''
    def _private_method():
        pass
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Instance Variables

Similar to methods, public instances should be in snake_case and private instances should begin with underscores(_)

class MyClass:
    pass

public_instance = MyClass()
_private_instance = MyClass()
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Functions

Functions should also follow snake_case

def func():
    pass

def func_one():
    pass
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Constants

Constant names must in all uppercase.

PI = 3.14
CONSTANT = 10
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It is just a naming convention. Python doesn't support constants.

Top comments (1)

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arvindpdmn profile image
Arvind Padmanabhan

Nice summary. Newbies can read PEP8: python.org/dev/peps/pep-0008/
For more general intro to naming conventions, read devopedia.org/naming-conventions