WEBVTT

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alright so there's one more thing that

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we need to talk about with these
alright so there's one more thing that

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properties and that's an alternate way
we need to talk about with these

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of coding them now in fact this
properties and that's an alternate way

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alternative method I'm going to show you
of coding them now in fact this

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is more common and you all probably more
alternative method I'm going to show you

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likely to see it when you read other
is more common and you all probably more

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people's python code now it
likely to see it when you read other

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uses something called decorators and
people's python code now it

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does exactly the same thing as we've
uses something called decorators and

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just seen it's just the syntax that
does exactly the same thing as we've

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differs now the decorator results in the
just seen it's just the syntax that

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property line being done for you which
differs now the decorator results in the

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is why people tend to prefer it to the
property line being done for you which

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method that we've seen in the previous
is why people tend to prefer it to the

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video you do need to be aware of both
method that we've seen in the previous

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approaches though and the way we've just
video you do need to be aware of both

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looked at it is easy to understand which
approaches though and the way we've just

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is why we started with that
looked at it is easy to understand which

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so let's see how to use this alternative
is why we started with that

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syntax by adding a property for our score
so let's see how to use this alternative

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attribute so we're going to go back to
syntax by adding a property for our score

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our player .py class and we're going to
attribute so we're going to go back to

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start off by hiding a score variable by
our player .py class and we're going to

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renaming to _score on line 7
start off by hiding a score variable by

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right-click the refactor rename will call it
renaming to _score on line 7

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_score you can see it also
right-click the refactor rename will call it

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change the line I changed the line
_score you can see it also

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25 as well which was also using score
change the line I changed the line

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the score data attribute now next thing we
25 as well which was also using score

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need to do is add the methods to get and
the score data attribute now next thing we

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set the score but we decorate those methods
need to do is add the methods to get and

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by putting a special comment before them
set the score but we decorate those methods

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going to add them after other methods
by putting a special comment before them

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before our
going to add them after other methods

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STR method down here so let's start
before our

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by putting....
STR method down here so let's start

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....
by putting....

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...
....

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...
...

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....
...

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....you can see what happened when we did
....

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that so that's it for the getter we add
....you can see what happened when we did

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the @ property decorator before the
that so that's it for the getter we add

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method on the previous line and the
the @ property decorator before the

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decorator takes care of the score equals
method on the previous line and the

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property line that we otherwise
decorator takes care of the score equals

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have to write now we haven't covered
property line that we otherwise

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decorators yet so just treat this as an
have to write now we haven't covered

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alternative syntax which it really which
decorators yet so just treat this as an

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is really all that it is now the method
alternative syntax which it really which

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can perform any other tasks it needs to
is really all that it is now the method

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so could multiply the score by the
can perform any other tasks it needs to

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number of lives left for example now the
so could multiply the score by the

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setter is also the same sort method
number of lives left for example now the

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that was used for the other setters the
setter is also the same sort method

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decorator this time is in the name of
that was used for the other setters the

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the property followed by dot setter so
decorator this time is in the name of

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we're going to come down here make a bit
the property followed by dot setter so

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of space here which will clean up a
we're going to come down here make a bit

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little bit afterwards we're going to
of space here which will clean up a

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type....
little bit afterwards we're going to

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....
type....

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...
....

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...
...

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let's clean this up a little bit now
...

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so again the setter method is the same
let's clean this up a little bit now

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sort of method that we've used for the
so again the setter method is the same

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other setters the difference here is
sort of method that we've used for the

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that the decorator i use this time when
other setters the difference here is

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the line prior to it is the name of the
that the decorator i use this time when

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property followed by dot setter you can
the line prior to it is the name of the

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see the line 37 now be careful though
property followed by dot setter you can

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on line 39 if you type self dot score
see the line 37 now be careful though

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equals score instead of self dot _
on line 39 if you type self dot score

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equals score you can get the same
equals score instead of self dot _

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recursive problem we had in the previous
equals score you can get the same

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video that applies to all the setters
recursive problem we had in the previous

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not just because we're creating this one
video that applies to all the setters

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differently so back in the main
not just because we're creating this one

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program main.py come down here and
differently so back in the main

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let's go ahead and do...
program main.py come down here and

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...we should find that
let's go ahead and do...

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works run
...we should find that

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see that's working fine and we've
works run

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got to score incremented or setter
see that's working fine and we've

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I should say to 500 so that is properties and
got to score incremented or setter

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getters and setters in python now
I should say to 500 so that is properties and

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there's really nothing to be gained from
getters and setters in python now

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making our score into a properly i just
there's really nothing to be gained from

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did it to show you this alternative
making our score into a properly i just

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syntax but getting back to the play.py
did it to show you this alternative

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while I'm talking but as the
syntax but getting back to the play.py

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class stares at the moment we could just
while I'm talking but as the

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have lifted accessing the score data
class stares at the moment we could just

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attribute directly now the setters for
have lifted accessing the score data

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lives and levels do perform useful
attribute directly now the setters for

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functions sso changing them to be
lives and levels do perform useful

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properties was a useful thing to do now
functions sso changing them to be

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the document
properties was a useful thing to do now

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for properties can be found at
the document

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this link that i'm going to paste into
for properties can be found at

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a browser
this link that i'm going to paste into

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you can see that it could be worth
a browser

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checking that out as well
you can see that it could be worth

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alright so I'm going to finish this
checking that out as well

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video here now in the next video we're
alright so I'm going to finish this

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going to start looking at inheritance
video here now in the next video we're

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which is an important and sometimes
going to start looking at inheritance

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overused feature of object-oriented
which is an important and sometimes

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programming see you in the next video
overused feature of object-oriented