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15 Python Tips : How to Write Code Effectively

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 Here are some Python tips to keep in mind that will help you write clean, efficient, and bug-free code.     Python Tips for Effective Coding 1. Code Readability and PEP 8  Always aim for clean and readable code by following PEP 8 guidelines.  Use meaningful variable names, avoid excessively long lines (stick to 79 characters), and organize imports properly. 2. Use List Comprehensions List comprehensions are concise and often faster than regular for-loops. Example: squares = [x**2 for x in range(10)] instead of creating an empty list and appending each square value. 3. Take Advantage of Python’s Built-in Libraries  Libraries like itertools, collections, math, and datetime provide powerful functions and data structures that can simplify your code.   For example, collections.Counter can quickly count elements in a list, and itertools.chain can flatten nested lists. 4. Use enumerate Instead of Range     When you need both the index and the value in a loop, enumerate is a more Pyth
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Sets Vs Lists Python Programmer Tips

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Sets Vs Lists Python Programmer Tips


Sets are only useful when trying to ensure unique items are preserved. Before sets were available, it was common to process items and check if they exist in a list (or dictionary) before adding them.

List example


Here unique is an empty list. Every time I compare with this list, and if it is not duplicated then the input item will append to the unique list. 

>>> unique = [] 
>>> for name in ['srini', 'srini', 'rao', 'srini']:
 ... if name not in unique: 
... unique.append(name) 
... >>> unique ['srini', 'rao']


There is no need to do this when using sets. Instead of appending you add to a set:

Set example


>>> for name in ['srini', 'srini', 'rao', 'srini']:
... unique.add(name) 
... 
>>> unique {'srini', 'rao'}


Just like tuples and lists, interacting with sets have some differences on how to access their items. You can't index them like lists and tuples, but you can iterate over them without issues. 


The only reason I use sets is to ensure there aren't any duplicates. If that is not needed, a list is preferable.


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