How to read and write files in Python?

Reading and writing files in Python is straightforward and commonly done using the built-in `open()` function. This function allows you to open a file and specify the mode in which you want to work with it, such as reading, writing, or appending. ### Reading Files To read a file, you typically open it in read mode (`'r'`). Here’s a simple example: ```python # Open a file for reading with open('example.txt', 'r') as file: content = file.read() # Read the entire file content print(content) ``` Using `with` is recommended because it automatically closes the file after the block is executed, even if an error occurs. You can also read a file line-by-line using a loop: ```python with open('example.txt', 'r') as file: for line in file: print(line.strip()) # Print each line without trailing newline characters ``` ### Writing Files To write to a file, open it in write mode (`'w'`). This will create the file if it doesn’t exist or overwrite it if it does: ```python with open('output.txt', 'w') as file: file.write("Hello, world!\n") file.write("This is a new line.") ``` If you want to add content to the end of an existing file without overwriting, use append mode (`'a'`): ```python with open('output.txt', 'a') as file: file.write("\nAppending this line.") ``` ### Summary of Common Modes - `'r'` – Read (default mode) - `'w'` – Write (overwrite) - `'a'` – Append - `'b'` – Binary mode (e.g., `'rb'` or `'wb'` for reading/writing binary files) These basics cover most file operations in Python. Remember to handle exceptions in production code to manage errors like missing files or permission issues.