Showing Revision 4 created 05/25/2016 by Udacity Robot.

1. Title:
   Updating the Design for Class Movie - Programming Foundations with Python
2. Description:

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   So in a previous lesson we created a class

   ¶

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   called movie. Now this class had the following attributes,
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   the movie's title, its storyline, a link to the
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   movie's poster image, and a link to its YouTube
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   trailer. Now in addition to these things, the class
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   movie also had a function called show_trailer. After we
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   had defined this class movie we created several instances
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    of this class. Instances like Toy Story and Avatar.
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    Now further imagine that we wanted to create
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    another class called TvShow. I would think that
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    this class would have details like the title
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    of the show, its season and episode number. And
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    also, the TV station that this show is
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    aired on. Additionally, this class could also have
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    a function called, get_local_listings. Once we've created a
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    class called TvShow, we can create multiple instances of
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    this class, instances like, season one, episode one
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    of Breaking Bad, and the final episode of Seinfeld.
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    Alright, so if we continue our thought experiment
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    here, we can further imagine that there can be
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    several items that both of these classes can
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    share amongst each other. Things like title for sure,
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    also things like duration of the movie and
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    duration of the TV show in minutes. So the
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    best way to structure this code would be
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    to create another class called Video, which would
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    have two attributes. The video's title, and the
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    video's duration. And the class Movie, could inherit from
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    this class Video. To do this, we would
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    have to add the class name Video, inside these
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    parentheses. Now, this would mean that class Movie,
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    would inherit title and duration, from class Video. Additionally,
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    the class TvShow could also inherit from class
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    Video. To do this we would also have
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    to add the class name Video inside these
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    parentheses. Now this would mean that class TvShow would
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    inherit title and duration from class video. Now
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    you can clearly see how we can write a
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    piece of code. In this case, class Video,
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    and continue to reuse it in multiple different places.
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    Another big benefit of writing code this way,
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    in addition to just reusing code, is that
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    it allows us to follow an intuitive model
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    of how things exist in our brain. So intuitively
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    speaking, we know what videos are, we also know what TV shows and movies are. So
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    writing code in this way allows programmers to
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    map how things exist in our brain onto code.