Example

If someone with access to windows and mac OS could test the methods this would be perfect

User should be able to change the default location for storing images

Here's a version of your nasa_background.py file but with a GUI added instead of command line.

I was thinking that previewing the image would be an easy next step to add. This could be done either with a "Preview" button in this window below that will popup a window with the image as a preview, or simply embedding the preview in the window itself.

Right now it simply displays the title and metadata.

from tools import nasa_api, background
import PySimpleGUI as sg

def nasa_gui():
    '''Get the newest NASA Picture of the Day and set it as background'''
    meta_info = nasa_api.get_info()

    layout = [  [sg.Text(meta_info['title'], key='-TITLE-')],
                [sg.Text(meta_info["explanation"], size=(50,0), key='-DESCIPTION-')],
                [sg.Button('Set'), sg.Button('Cancel')]]
    window = sg.Window('NASA Picture of the Day', layout)
    event, values = window.read()
    window.close()
    if event == 'Set':
        file_path = nasa_api.download_image()
        background.change_background(file_path)


if __name__ == '__main__':
    nasa_gui()

The user should be able to choose from pictures from different dates if specified

The user should be able to change the default key to their personal key. The key should be saved and the user should be able to reset the key to 'DEMO_KEY'.

Sometimes, the media type is video. The program currently bugs in tools.nasa_api.download_image(), when the 'hd_url' key is not present in the meta_info dictionary.

The program should tell the user that for this chosen day, there is no picture available.

Issue can be recreated by attempting to download the image for 2019-12-23

Write the tests for nasa_api functions get_info and download_image

I think it would be useful to be able to schedule to update task with either a cron job or task scheduler. For this to work completely automatically, the user should not be prompted anything when the --auto option is activated.