How to open a file in python

To open a file, use the open() function, which requires the file name and a pattern string. Commonly used modes include: 'r' (read only), 'w' (write and overwrite), 'a' (append), 'r ' (read and write), 'w ' (write, read and overwrite), 'a ' (append and read and write). Remember, you need to close the file using the close() method to release resources.

How to open a file in Python

Let’s get straight to the point: In Python, use open() Function opens a file.

Details:

open() The function requires two parameters:

• File name ：The name of the file to be opened
• Mode:A string specifying how to open the file

Common mode:

• 'r': Open the file in read-only mode
• 'w': Open the file in write mode. If the file does not exist, a new file will be created. If the file exists, the original content will be overwritten.
• 'a': Open the file in append mode. If the file does not exist, a new file will be created. If the file exists, the contents will be appended to the end of the file.
• 'r ': Open the file in read-write mode. Allows reading and writing the contents of the file.
• 'w ': Open the file in write and read mode. Similar to 'w' mode, but once the file is open, the contents can be read and written.
• 'a ': Open the file in append and read modes. Allows reading and writing the contents of the file, and appending content to the end of the file.

Example:

The following example opens the "myfile.txt" file in read-only mode:

<code class="python">f = open("myfile.txt", "r")</code>

The following example opens in write mode Open the "myfile.txt" file:

<code class="python">f = open("myfile.txt", "w")</code>

The following example opens the "myfile.txt" file in append mode:

<code class="python">f = open("myfile.txt", "a")</code>

Note:

• Opened files must be closed to release system resources. Files can be closed using the close() method.
• If the file does not exist and an attempt is made to open it in 'r' mode, the open() function will raise a FileNotFoundError exception.
• If the file exists and an attempt is made to open it in 'w' or 'a' mode, the open() function will overwrite or append to the contents of the existing file.

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