WEBVTT

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in the previous video we did our
first part of the challenge and that's

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where we set up this cave underscore initialize dot py
which ultimately save

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our locations and vocabulary
dictionaries to convert them to shelves

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what we wanna do now is we want to change
the code that runs the game the actual

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game itself and make the changes so that
instead of using a dictionary it uses

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the shelves created we created in this so what I'm going
to do is go back to

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challenge you see that cave_game.py that is the file name we want to use for the

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game part of it so we are going to
create that new python and its going to be

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cave_game.py and what I'm gonna
start with is just a copy this code in line 45

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from the challenge.py through to the
end and paste that to

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cave_game.py so that's the basic
game so obviously we got some erros showing

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at the moment because we haven't got the
locations and the vocabulary set up so we

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need to actually do that we need to come
up here initially on line 1 we need to

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import shelve of course because we are going to use the shelve module.....

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and the other thing we need
to do while we remember is down here we ill close

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them so....always have to do that

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remember, if we are not using with to close things manually which is we have done there

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the other change we need to make is on line 6
you notice it currently we got loc equals

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one and that's an integer I want to
change that so its initialize to a

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string because of course if you recall
in cave_initilaize.py we

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set it up so we will use strings because
of course shelves need to use strings

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as keys s so because locations is gonna
be key ultimately that will need to be

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a string so I'm gonna put single quotes around that
 so that is now a string and the other thing we need to do then

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is on line 12 we're testing to see
whether 0 has been received

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because it's a string we need to do a test
against a string string comparison and

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that's going to be two single quotes to do that comparison now

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that should be it so what we'll do is
we'll give this a run just to make sure

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that does work and I'm going to run this
the first time so that, and just check

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the I called that he correct name......vocabulary that should be correct we will just

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run it again you can see the problem here was in a line 8
so lets checked that out

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and we acutally see that so lets close this down so it is having a
problem there with line 8 at which is

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available exits and the
problem is if we run it again to check, it is

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having a problem with the keys
themselves so let's go back to cave_initialize

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just to make sure that I
haven't messed up something and that seems

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that I've made that error again the one I made about
three or four times or more in this

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course is of course when I ran the
initialize hadn't been set up the first

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time and I can see that it hasn't been set
up so consequently the error we are getting

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here when we run these cave_game I'm running
now is basically saying well those files

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don't exists and the reason they don't
exist is of course I didn't run it so

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what happened was the challenge code
was actually run or actually more likely the

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example.py was run and I wasn't
really paying attention to the screen

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which I should have so what we need to
do now is go back to cave_initialize.py

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that's correct as it is right click
that run cave_initialize that's going to

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create a our shelves witch I should have
done and then go back to cave_game than

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any other code changes we should be able to run that as well and now we are not getting an error what a surprised Tim if you acutally rung the right file it might work

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and we will do a bit a testing to make sure that
it's working

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so go north and we're getting an error
there and ok int object has no attribute

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I think what I've done is I've forgotten to
change something in the cave_initialize

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so I'll close this down and go
back and have a look and actually what I

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haven't done which I should have done
you notice we are using a key for the locations it

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was an integer and I change this correctly to a string but the location

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is also used in the exits as you can see
in the named exits and I haven't changed

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the value to a string now the values has to be
string because we gonna be comparing the

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string value here to the location we entered there so we could convert

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that to an integer but  probably the
best practices because we are gonna be

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continually converting it to get the
data right the first time so in that

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situation I recommend you do is you
changed the data type your going to be using

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which in this case is gonna be
string so I'm gonna change all of these

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to strings...and that should fix the problem once we are done with it

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you can see that IntelliJ tries to be helpful

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I've put a single quote around before a number that's fine but if I put it after it adds two because it thinks you

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wanna put some numbers something in the
middle of it so it all a matter of cursor

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position to get this right

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....and we should find that it will work after we do this, couple more to do, and that should be that so what we've done is we've
converted

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hopefully all of them hopefully I didn't miss some strings and actually there is a couple I miss

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there Tim what are you doing? so now I think we are done, no there is still another one, goodness I'm having a bad day

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Ok I cannot see any more now so what we're
going to do is rerun this we should recreate

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the shelve and then when we go back to cave and its going to work
so again just to be clear the reason it

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wasn't working

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was we converted the locations two
strings here and then in here we had a

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location and direction to go to but we
also had the location stores integer so

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what was happening was there was a
string integer comparison taking place

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in here so it successfully printed
it out but when we try to do a comparison but we ultimately

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crash because it was that string and
int comparison that is occurring in game so

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lets go back to first to cave_initialize right click that and run that to

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recreate the shelve that's been done so if we go back to cave_game
right click and run that a see if its going to

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work for us so type north south east west will
try typing north that's good and try typing quit

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and that is it so

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albeit with a bit of bother we got to actually the
end and I managed to get this working so

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that's good so that was our solution the solution 
myself and JP came up with so hope you

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enjoy that and what was quite
interesting I felt was that really there is

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very few changes required to the actual
game so we swipe out the dictionary

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that was in the game

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quite easily by replacing the lines 3 and 4, 34 and 35 and we had to little tests

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we need to change we need to
change the test on line 12

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and also change the variable type from
an integer to a string on line 6 and of

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course the bulk of the changes
were in the data in this format where we

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actually wrote the correct
dictionaries to shelves so this is

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what we always recommend you do is get
you data correct so don't write the

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program to sort of manipulate problems
in the data so in other words what

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I could have done there was I mention
when I was converting these which

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should have been two strings by putting
the single quotes around them we could

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come back to the code here and
started doing a comparison and checking

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converting integers back to strings and
so forth and doing comparison like that

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but that would all be sort of coding to
cover up the fact that time we made a

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mistake with our data by getting the
data correct it means we don't have

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to do any extra coding in the game and that
applies to a lot of coding in general

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getting the data correct is a great first step
to being able to with a minimal amount of

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code go through and manipulate use that data as we did so as it
turns out there's very few lines of code

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that were needed to get the
game working with shelves so that's it

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that's the shelve challenge I hope you've
enjoyed that so that's actually also the

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end of this section so in the next
section we gonna be starting to talk

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about modules and functions so we look
forward to taking you through that and

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we'll see you in the next section