Text Modifier - Python Programming Exercise

import sys

def replace_text_in_file(file_name, target_word, replacement_word):
    """
    Reads a text file, replaces all occurrences of the target word with the replacement word,
    and saves the modified content into a new file named 'file_name.out'.
    
    Parameters:
    file_name (str): The name of the input file to read.
    target_word (str): The word to be replaced.
    replacement_word (str): The word to replace the target word with.
    """
    try:
        # Open the input file in read mode
        with open(file_name, 'r') as file:
            # Read all the lines from the file
            content = file.read()
        
        # Replace all occurrences of target_word with replacement_word
        modified_content = content.replace(target_word, replacement_word)
        
        # Create the output file name by appending '.out' to the original file name
        output_file_name = file_name + '.out'
        
        # Open the output file in write mode and save the modified content
        with open(output_file_name, 'w') as output_file:
            output_file.write(modified_content)
        
        print(f"Modification successful! The modified content has been saved to '{output_file_name}'")
    
    except FileNotFoundError:
        print(f"The file '{file_name}' was not found.")
    except Exception as e:
        print(f"An error occurred: {e}")


# Main program execution
if __name__ == "__main__":
    # Check if the correct number of arguments are provided
    if len(sys.argv) != 4:
        print("Usage: replace_text   ")
    else:
        # Extract command-line arguments
        file_name = sys.argv[1]
        target_word = sys.argv[2]
        replacement_word = sys.argv[3]
        
        # Call the replace_text_in_file function
        replace_text_in_file(file_name, target_word, replacement_word)

 Output

Assume file.txt contains the following text:
hello world
hello there
hello again

If you run the following command:
python replace_text.py file.txt hello goodbye

The program will create a new file, file.txt.out, with the following content:
goodbye world
goodbye there
goodbye again