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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 Use List Function in Python

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Here's is an answer to calculate the length of the repeated lists. LIST is a principle data type in Python that holds a list of values. Usually strings.

List() Function the Real Usage

You can do various operations with Lists. The best examples are REPEAT, APPEND, INSERT, EXTEND, COUNT. Still more you can do.


Note: This question is from a test recently held by an HR company. HR firms usually ask to take an online test to filter the job-seekers.

You can find list length using list() and len() functions


IN THIS PAGE


1. Question
2. How to Find Length


Interview Question 

The '* 2' says times the list is repeated. In this question, they have given '2' times.


my_list = ['srini', 'seetha', 'rao']
b = len(list(list(list(list(list(my_list*2))))))
Print (b)


Select Answer

1. 5
2. 6
3. 7
4. None

Explanation:

  • In the first step, the '*' says, you repeated the List two times.
  • It confuses the test-taker since they have given multiple functions of the list().

How to get Length


You can code the way I did. So that you can get the length correctly. So, the answer to the question is '6'. The List is repeated twice. There's no effect of multiple lists on the list.


Result (Ubuntu Linux OS)


At the command level, the given question entered. After pressing enter, it showed the result as '6'. That means the list (which has initially '3' elements') doubled. So the list length is now '6'.


Result of Python List

References

  1. Here're the best examples on Python List
  2. Here's the complete list for your reference.

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