1. This file declares a class, `Player`, instantiates it, and assigns it to a global `const player` variable.
2. The `Player` class contains four methods:
    - `constructor()`
    - `playPause()`
    - `skipTo()`
    - `setVolume()`
3. The `constructor()` method sets initial values for the `currentlyPlaying`, `playState`, `volume`, and `soundObject` properties.
    - `currentlyPlaying` is set to the first item in `album.songs`.
    -  The initial `playState` is `"stopped"`.
    -  The `volume` is set to the number `80`.
    -  The `soundObject` instantiates a new `buzz.sound` object using the `soundFileUrl` property of `this.currentlyPlaying`. The `buzz` variable doesn't appear to be initialized here, so presumably it's a dependency loaded elsewhere.
4. The getDuration() method returns this.soundObject.getDuration(). It appears to be a wrapper for a method available on this.soundObject.
5. The getTime() method returns this.soundObject.getTime(). It also appears to be a wrapper for a method available on this.soundObject.
6. The `playPause()` method accepts one parameter, `song`. It sets it to `this.currentlyPlaying` by default.
  * It checks to see if `this.currentlyPlaying` is different from `song`, and if so, it:
    - Stops the `soundObject` property.
    - Removes the `"playing"` and `"paused"` classes from the `element` property of `this.currentlyPlaying`.
    - Sets `this.currentlyPlaying` to the function's parameter, `song`.
    - Changes the `playState` property to `"stopped"`.
    - Instantiates a new sound object using `this.currentlyPlaying`, which was just updated to `song`.
  * Then, if `this.playState` equals `paused` or `this.playState` equals `stopped`:
    - Sets volume by passing property `this.volume` to method `setVolume`
    - Executes API method `this.soundObject.play()`
    - Sets property `this.playState` to `'playing'`
    - Removes the `"playing"` and `"paused"` classes from the `element` property of `this.currentlyPlaying`.
  * Otherwise:
    - Exucutes API method `this.soundObject.pause()`
    - Sets property `this.playState` to `'paused'`
    - Removes the `"pausesd"` and `"playing"` classes from the `element` property of `this.currentlyPlaying`.
7. Method `skipTo` accepts one parameter, `percent` to execute the following logic:
  * If `this.playState` does not equal `playing`, then the method executes a void return.
  * Otherwise, it sets the play position by passing the product
      `percent / 100` × the return value of API method `this.soundObject.getDuration()`
  as the parameter to the API method `this.soundObject.setTime`
8. Method `setVolume` accepts one parameter, `percent` to:
    - set property `this.volume` to `percent`
    - set the volume by passing `percent` as the parameter to the API method `this.soundObject.setVolume`