How Can I Read a File Line by Line into a List in Python?

Reading a File Line-by-Line into a List in Python

Storing each line of a file as an element in a list is a common task in Python. To achieve this, you can use the open() function with a loop that iterates through each line of the file.

Method:

To read a file line-by-line and append each line to a list, follow these steps:

1. Use the open() function to open the file and specify the read mode ('r').
2. Loop through the file object using a for loop.
3. In each iteration, use the rstrip() method to remove any trailing whitespace characters from the current line.
4. Append the cleaned line to the list.

Code:

with open(filename, 'r') as file:
    lines = [line.rstrip() for line in file]

Alternatively:

If you prefer to iterate over the file object directly and print each line, you can use the following code:

with open(filename, 'r') as file:
    for line in file:
        print(line.rstrip())

Python 3.8 and Later:

In Python 3.8 and later, you can use the walrus operator ('=') to streamline the code:

with open(filename, 'r') as file:
    while line := file.readline():
        print(line.rstrip())

Additional Notes:

• The with block automatically handles file opening and closing.
• If you need to specify the access mode and character encoding, you can modify the open() call as follows:

with open(filename, 'r', encoding='UTF-8') as file:

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