How do I extend a python module? Adding new functionality to the `python-twitter` package

Question

What are the best practices for extending an existing Python module – in this case, I want to extend the python-twitter package by adding new methods to the base API class.

I've looked at tweepy, and I like that as well; I just find python-twitter easier to understand and extend with the functionality I want.

I have the methods written already – I'm trying to figure out the most Pythonic and least disruptive way to add them into the python-twitter package module, without changing this modules’ core.

Answer 1

A few ways.

The easy way:

Don't extend the module, extend the classes.

exttwitter.py

import twitter  class Api(twitter.Api):     pass      # override/add any functions here. 

Downside : Every class in twitter must be in exttwitter.py, even if it's just a stub (as above)

A harder (possibly un-pythonic) way:

Import * from python-twitter into a module that you then extend.

For instance :

basemodule.py

 class Ball():     def __init__(self,a):         self.a=a     def __repr__(self):         return "Ball(%s)" % self.a  def makeBall(a):     return Ball(a)  def override():     print "OVERRIDE ONE"  def dontoverride():     print "THIS WILL BE PRESERVED" 

extmodule.py

from basemodule import * import basemodule  def makeBalls(a,b):     foo = makeBall(a)     bar = makeBall(b)     print foo,bar  def override():     print "OVERRIDE TWO"  def dontoverride():     basemodule.dontoverride()     print "THIS WAS PRESERVED" 

runscript.py

import extmodule  #code is in extended module print extmodule.makeBalls(1,2) #returns Ball(1) Ball(2)  #code is in base module print extmodule.makeBall(1) #returns Ball(1)  #function from extended module overwrites base module extmodule.override() #returns OVERRIDE TWO  #function from extended module calls base module first extmodule.dontoverride() #returns THIS WILL BE PRESERVED\nTHIS WAS PRESERVED 

I'm not sure if the double import in extmodule.py is pythonic - you could remove it, but then you don't handle the usecase of wanting to extend a function that was in the namespace of basemodule.

As far as extended classes, just create a new API(basemodule.API) class to extend the Twitter API module.

Answer 2

Don't add them to the module. Subclass the classes you want to extend and use your subclasses in your own module, not changing the original stuff at all.