How to Write Newlines to a File in Python

What are the methods to write a newline into a file using Python?

with open('output.txt', 'w') as file:
    file.write('Hello, World!\n')
    file.write('This is a new line.\n')

Writing newlines to a file in Python is a straightforward task that can be accomplished using the built-in `open()` function in conjunction with the `write()` method. This allows you to create or write to a text file and control the formatting of your output, including inserting newlines where necessary.

# Writing to a file with newlines in Python
with open('output.txt', 'w') as file:
    file.write('First line\n')  # Adding a newline after this line
    file.write('Second line\n')  # Adding a newline after this line
    file.write('Third line')  # No newline after this line, it will be the last line.

Causes

• Using an incorrect file mode (e.g., 'r' instead of 'w') can prevent writing to the file.
• Not including `\n` in the strings to create a newline.

Solutions

• Use the correct file mode: 'w' for writing, 'a' for appending.
• Explicitly include the newline character '\n' in your strings. For example: `file.write('Line 1\n')`.
• Use triple quotes for multi-line strings, which automatically include newlines.

Mistake: Omitting the newline character '\n' when writing lines.

Solution: Always append '\n' at the end of each string unless it's the final line.

Mistake: Using 'w' mode instead of 'a' mode when wanting to preserve existing content.

Solution: Use 'a' if you want to append new lines without overwriting existing content.