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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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Python - How to Lookup Dictionary by Key

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Here's Python Dictionary that explained how to lookup it using Key. Dictionary in Python is Key/Value pair. It's different from the list. The basic rule to identify; is enclosed in flower brackets ({}). Here's a demo about lookup and how to test it. 


Dictionary = { 'key' : 'value', 'key: value'  }  


Dictionary Lookup


IN THIS PAGE

  1. Python Dictionary
  2. Python Lookup
  3. How to check Lookup working or not

Dictionary


Example

my_dict = {'name' : 'srini' , 'salary' : '100000', 'skills' : 'python' }

Here, 'name' is the label.

Then, :

Then, 'srini' -> Value

Explanation
  • Data is enclosed in flower brackets
  • It's an unordered list
  • You can manipulate data (mutable)
  • You can access the value of a particular key. So, in Python, it's called a Lookup. It's one of the best interview questions.



Lookup Dictionary by Key

Python Lookup (a.k.a Dictionary). You can access data quickly. It's really super-speed. 

my_dict['name']

The result will be: 'srini'

  • You should use square brackets ([]) to get lookup data
  • Use key-value in square brackets ([]) with a single quote, you will get value


Output from Lookup

I am now adding new value to the Lookup.

>>> my_dict['role'] = 'Manager'

Now, the my_dict will'be :

>>> my_dict = {'name' : 'srini' , 'salary' : '100000', 'skills' : 'python' , 'role' : 'Manager'}

  • The order of assignmenet will not match with actula storing in Python
  • The order of Key/Value storage is taken care by interpreter

References

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