appending column names to file

To append column names to a file, you can use the following steps:

1. Open the file in append mode using the open() function.
2. Write the column names to the file using the write() function.
3. Close the file.

Here's an example code snippet:

# column names
cols = ['Name', 'Age', 'Gender']

# open file in append mode
with open('data.txt', 'a') as file:

    # write column names to file
    file.write(','.join(cols) + '\n')

# close the file
file.close()

In this example, we have a list of column names called `cols`. We then open the file called `data.txt` in append mode using the `with open()` statement. We write the column names to the file using the `write()` function, joining the column names with commas and adding a newline character at the end. Finally, we close the file using the `close()` function.

After running this code, the column names will be appended to the end of the file.