Showing Revision 8 created 05/25/2016 by Udacity Robot.

1. Cím:
   What Is Going On Behind the Scenes - Programming Foundations with Python
2. Leírás:

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   Okay, so here is the code for the class Movie
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   that we have written thus far. Now, bear in mind, that
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   you may have to go into full-screen mode in order
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   to see all of the details here properly. And I'm really
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   curious to figure out what happens behind the scenes when
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   I run this line of code. What happens when I create
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   an instance called toy_story by providing these four pieces of
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    information or arguments. These pieces of information are the name of
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    the movie, its story line, the link to its poster,
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    and the link to its YouTube URL. Now clearly, the
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    last two of these are not really links or URLs
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    just yet. They are English phrases and I did that because
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    there wasn't enough space on the screen for me to
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    add the full links or the URLs to the poster and
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    the YouTube trailer. So, the first thing that happens when
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    we learn this line of code is that the init function
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    gets called. And the init function, you
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    will recall, is the function we defined inside
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    class Movie. Self, in that case, is itself
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    or the instance being created, which is toy_story.
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    The next argument is movie_title whose value
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    is Toy Story. Movie_storyline gets the value Toys
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    come to life. The variable poster_image gets the
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    right value. And finally, the trailer_youtube variable gets
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    the correct link. Okay, so far so good. Now, once init gets called and
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    all of these arguments receive their correct
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    values, all of the variables that are associated
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    with the instance toy_story, they get initialized
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    appropriately and these variables, you may notice,
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    are title, storyline, poster_image_url and trailer_youtube_url. At
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    this point, if I try to print out
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    toy_story.storyline, it prints out the correct value. All right,
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    now that we know exactly what happens when we create
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    this instance toy story. Let's go back to our
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    design and find out what we have to do next.