How do I python append to file instead of overwriting it?

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#1

How do I Python append to a file instead of overwriting it?

#2

Hey @Jasminepuno

Hope you are doing well, Here is the detailed explanation:-

When you need to add content to a file without overwriting the existing data, you can open the file in append mode using the ‘a’ flag. This will allow you to add new content at the end of the file.

Here’s an example:

with open('file.txt', 'a') as file:
    file.write("This is the new content added at the end.\n")

Explanation: The 'a' mode opens the file for writing at the end, ensuring the new content is added without deleting the existing data. If the file doesn’t already exist, it will be created. Using the with statement guarantees that the file is closed automatically once writing is done.

Thanks!

#3

Hey All!

If you’re looking to append multiple lines at once, you can use the writelines() method while still in append mode. This is a great way to efficiently add several lines to the file.

Example:

lines_to_append = ["Line 1\n", "Line 2\n", "Line 3\n"]
with open('file.txt', 'a') as file:
    file.writelines(lines_to_append)

Explanation: The writelines() method writes a sequence of lines to the file. Just keep in mind, it doesn’t automatically add newlines between each line, so you need to ensure that each line you provide ends with \n if necessary.

Thank you!

#4

An alternative method to append data to a file is by using the print() function, specifying the file argument. This allows you to append text without having to explicitly call write().

For example:

with open('file.txt', 'a') as file:
    print("This is appended via print.", file=file)

By specifying the file parameter in the print() function, the content is written directly to the file, appending the text at the end without overwriting the existing content. This is a convenient approach when working with dynamic data that needs to be printed into a file.