Now you know all about files! You were able to:

• Open up file objects using open() and with.
• Read a file’s full contents using Python’s .read() method.
• Read a file line-by-line using .readline() and .readlines()
• Create new files by opening them in write-mode.
• Append to a file non-destructively by opening a file in append-mode.
• Apply all of the above to different types of data-carrying files including CSV and JSON!

You have all the skills necessary to read, write, and update files programmatically, a very useful skill in the Python universe!