Add text to list Python

Summary: in this tutorial, youll learn how to write to text files in Python.

TL;DR

The following illustrates how to write a string to a text file:

Steps for writing to text files

To write to a text file in Python, you follow these steps:

• First, open the text file for writing [or appending] using the open[] function.
• Second, write to the text file using the write[] or writelines[] method.
• Third, close the file using the close[] method.

The following shows the basic syntax of the open[] function:

The open[] function accepts many parameters. But youll focus on the first two:

• The path_to_file parameter specifies the path to the text file that you want to open for writing.
• The mode parameter specifies the mode for which you want to open the text file.

For writing to a text file, you use one of the following modes:

The open[] function returns a file object. And the file object has two useful methods for writing text to the file: write[] and writelines[].

The write[] method writes a string to a text file and the writelines[] method write a list of strings to a file at once.

In fact, the writelines[] method accepts an iterable object, not just a list, so you can pass a tuple of strings, a set of strings, etc., to the writelines[] method.

To write a line to a text file, you need to manually add a new line character:

And its up to you to add the new line characters.

Writing text file examples

The following example shows how to use the write[] function to write a list of texts to a text file:

If the readme.txt file doesnt exist, the open[] function will create a new file.

The following shows how to write a list of text strings to a text file:

If you treat each element of the list as a line, you need to concatenate it with the newline character like this:

Appending text files

To append to a text file, you need to open the text file for appending mode. The following example appends new lines to the readme.txt file:

Output:

Writing to a UTF-8 text file

If you write UTF-8 characters to a text file using the code from the previous examples, youll get an error like this:

To open a file and write UTF-8 characters to a file, you need to pass the encoding='utf-8' parameter to the open[] function.

The following example shows how to write UTF-8 characters to a text file:

Summary

• Use the open[] function with the w or a mode to open a text file for appending.
• Always close the file after completing writing using the close[] method or use the with statement when opening the file.
• Use write[] and writelines[] methods to write to a text file.
• Pass the encoding='utf-8'to the open[] function to write UTF-8 characters into a file.