Human: Python function to add something to a text file in Python. Assistant: 
Here is a Python function to add something to a text file

import os

def add_to_file(file_name, text):
    """
    Add text to a file.
    """
    with open(file_name, 'a') as f:
        f.write(text)

# Enter the file name
file_name = 'test.txt'

# Enter the text to be added
text = 'This is a test'

# Calling the function
print((add_to_file(file_name, text)))

#Example Output
# None

#Remember to inspect code for bugs.