Question 28 (Choice 1) - CBSE Class 12 Sample Paper for 2024 Boards - Solutions to CBSE Sample Paper - Computer Science Class 12

Write a function in Python to read a text file, Alpha.txt and displays those lines which begin with the word ‘You’.

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Answer by student

Detailed answer by teachoo:

• The question asks us to write a function in Python to read a text file and display those lines which begin with the word ‘You’.
• To do this, we need to use the following steps:
• Open the file using the open() function, which takes the file name and the mode as arguments. The mode can be “r” for reading, “w” for writing, “a” for appending, or “r+” for both reading and writing. In this case, we use “r” mode to read the file.
• Loop through each line in the file using a for loop. The open() function returns a file object that can be iterated over using a for loop.
• Check if the line starts with the word ‘You’ using the startswith() method, which takes a string as an argument and returns True if the string starts with that argument, or False otherwise. For example, “You are awesome”.startswith(“You”) returns True, but “I am awesome”.startswith(“You”) returns False.
• If the line starts with ‘You’, print the line using the print() function, which displays the value of its argument to the standard output. We use the end parameter of the print() function to specify what to print at the end of each line. By default, it is a newline character (\n), which means that each print() statement will print a new line. However, since the lines in the file already have a newline character at the end, we don’t want to print another one. So we set the end parameter to an empty string (“”). This way, we can print each line as it is in the file.
• Close the file using the close() method, which frees up any system resources used by the file object. It is a good practice to close any files that we open after we are done with them.

So, the correct answer is: