We are going to implement a music library + crawler for the music on our computer.

First, we are going to need a Song class which we want to initialize like that:

s = Song(title="Odin", artist="Manowar", album="The Sons of Odin", length="3:44")

Length can have hours!:

Those are all valid lengths:

• "3:44"
• "1:30:44"

The methods we want for our Song are:

• __str__ - should be able to turn the song into the following string: "{artist} - {title} from {album} - {length}"
• Our Song should be hashabe! Implement __eq__ and __hash__
• length(seconds=True) should return the length in seconds.
• length(minutes=True) should return the length in minutes (omit the seconds)
• length(hours=True) should return the length in hours (omit minutes and seconds that does not add up to a full hour)
• length() should return the string representation of the length

We are going to implement a collection for our songs.

The playlist should be initialized with a name:

code_songs = Playlist(name="Code", repeat=True, shuffle=True)

• repeat should be defaulted to False
• shuffle should be defaulted to False

The Playlist should behave like that:

• add_song(song) and remove_song(song) are self explanatory.
• add_songs(songs) should add a list of songs.
• total_length() should return a string representation of tha total length of all songs in the playlist
• artists() - returns a histogram of all artists in the playlist. For each artist, we must have the count of songs in the playlist.
• next_song() should return a Song instance from the order of the playlist. If repeat=True, when our playlist reaches the end, it should loop back again at the beginning. If shuffle=True, everytime we call next_song(), we should get a different song. Make it randomize so it wont repeat a played song unless every song from the playlist has been played!
• pprint_playlist() should print the playlist to the console in a table-like view. Here is an example:

| Artist  | Song             | Length |
| --------|------------------|--------|
| Manowar | Odin             | 3:44   |
| Manowar | The Sons of Odin | 6:26   |

We should be able to save and load a playlist to a JSON file.

• save() should be a instance method, that saves the playlist to a JSON filed, which has the name of the playlist. If the name has whitespaces in it, replace them with "-" - the so-called dasherize.
• load(path) should be a @staticmethod that returns a new Playlist instance.

Example usage:

code = Playlist("For Code")
# ... adding songs ...

# Saves to For-Code.json
code.save()

Later on:

code = Playlist.load("For-Code.json")
code.name == "For Code" # True

Save the *.json files in a specified folder, for instance, called playlist-data. Make the load function look there too.

Create a MusicCrawler class that creates playlists and songs objects from real files on your file system. Most of .mp3 and .ogg files have tags that describe them. Tags hold information about the title, artist, album etc. Our task is to crawl a directory full of .mp3 or .ogg files and create a new playlist by reading the files' tags.

We recommend you mutagen to read audio metadata

Example:

>>> crawler = MusicCrawler("/home/ivaylo/Music/")
>>> playlist = crawler.generate_playlist()

As you see, the constructor takes only one argument - the path of the directory from which you should read all the audio files.

generate_playlist() method craws all the files and returns a new playlist full of songs.

This is a hard problem. Solve only if you want to.

If you want to make this program usable you should implement a console interface for it. You don't have to test this class! Implement this in the way you like it. Make it as user friendly as a console can be.

This class should only parse user commands and call methods from the above classes.

In order to play music from the console, you can use whatever you want to use on the internet!