• Practice using file IO.
• Execute and test Python code using the Python shell and pytest.

• Module: a file containing Python definitions and statements. A module's functions, classes, and global variables can be accessed by other modules.
• Package: a collection of modules that can be accessed as a group using the package name.
• import: the Python keyword used to access data from other packages and modules inside of the current module.
• PyPI: the Python Package Index. A repository of Python packages that can be downloaded and made available to your application.
• pip: the command line tool used to download packages from PyPI. pip is installed on your computer automatically when you download Python.
• Virtual Environment: a collection of modules, packages, and scripts that can be activated or deactivated at any time.
• Pipenv: a virtual environment tool that uses pip to manage the modules, packages, and scripts that you intend to use in your application.

In the last lesson we learned about the tools that can help us work with files. Creating and manipulating files is a crucial skill that can help you create useful and complex programs. In this lab we will explore file IO.

Lets practice! In the file file_io.py write a function called write_file that takes in the arguments file_name and file_content.

The file_name can be a combined file path/name, you will need to add the file extension to the file_name when opening a file.

This function should use file_name included and file_content to write a .txt file.

Write a append_to_file function that takes in the same parameters and appends to the .txt file.

Write a read_file function that takes in a file name and returns the content of the .txt file.

Example usage:

# use write_file function. 
write_file(file_name="logfile", file_content="Log 1: 5 bananas added" )
append_file(file_name="logfile", append_content="Log 2: 3 bananas subtracted")

read_file(file_name="logfile")
# Log 1: 5 bananas added
# Log 2: 3 bananas subtracted

Time to get some practice! Write your code in the file_io.py file in the lib/ folder. Run pytest -x to check your work.

When all of your tests are passing, submit your work using git.

• Python File IO