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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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How to Explain String Immutability in Python Correctly

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Here is an answer to explain the immutability of Strings in Python. It means that you can't modify the string. Due to this, you can use strings securely in many places of your project.


Strings Immutability


How to check string immutability

Here is an example. In the python shell, assign a value of your choice to a string. Here my choice is ABCD, and I have assigned it to myString. I have tried to replace A with Z. But, it gave an error due to the immutability of strings.


>>> myString = 'ABCD'
>>>myString [0] = 'Z'


What is learning here

The strings immutability is an interview question. In interviews, you can say that strings are immutable, and you can't replace its data.

Benefits of strings immutability

  1. It saves a lot of time since the data in strings are immutable. It results in high performance.
  2. String objects you can reuse as no one can modify its value.
  3. Strings are elemental. So no activity can change its value ( these are more like numbers).

References

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