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Step-by-Step Guide to Reading Different Files in Python

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 In the world of data science, automation, and general programming, working with files is unavoidable. Whether you’re dealing with CSV reports, JSON APIs, Excel sheets, or text logs, Python provides rich and easy-to-use libraries for reading different file formats. In this guide, we’ll explore how to read different files in Python , with code examples and best practices. 1. Reading Text Files ( .txt ) Text files are the simplest form of files. Python’s built-in open() function handles them effortlessly. Example: # Open and read a text file with open ( "sample.txt" , "r" ) as file: content = file.read() print (content) Explanation: "r" mode means read . with open() automatically closes the file when done. Best Practice: Always use with to handle files to avoid memory leaks. 2. Reading CSV Files ( .csv ) CSV files are widely used for storing tabular data. Python has a built-in csv module and a powerful pandas library. Using cs...
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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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