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Great! The program is going well. I hope
you enjoying this! It's not a big program

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so we don't have lots of code here but
however in this implements quite a lot

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of aspects of Python, so we're loading
data in Python, into a Python data type

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and we have functions, we have
conditionals here, we have user input, and

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later we also going to implement for
loops in this code. So we'll talk about

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that later,
why we need for loops. And so we have

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libraries, we're reporting libraries here.
And so this is JSON. We also

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need to import a difflib library which we
are currently working on, so let's focus

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on difflib for now and what we
have is you know we passed this rainn

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string with double n here and we got a
set of suggestions so the best matches

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of the word rain out of the keys of our
dictionary, but you may also pass a word

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that doesn't exist at all and it doesn't
have any similar matches there like that.

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So basically you have three scenarios.
The user enters the exact word like rain

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and immediately you return data, so with
that particular key. That's the first

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scenario. The second scenario is when
user enters a word that is very close to

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one of the words you have in your
dictionary so like rain with an extra N.

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In that case you want to return the
first item of the list that the

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get_close_matches generates.
And the third scenario is when you get

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an empty list which means that there is
no such word or similar to that in your

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list and so we have three scenarios
which means we need to sort of apply

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three conditionals in the conditional
block here. At the moment we have only

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two so we need one more which says:
�Did you mean this word?

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Please double check it�. For now we'll
just will just pass a message and also

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note something. You may also want to pass
a higher cutoff value there like 0.8

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because you know sometimes if this is a
low like 0.5 and you pass like some

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random word, that will suggest you a few
words which maybe you don't want so you

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may want to play around with that. In
that case you get an empty list. I think

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I'll use a 0.8 value for the cutoff
when I implement it in the script here.

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So let's go to our code. The first
thing we need to check is if the word is

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in data and return the value for that
word. You may ask what if you want to

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check for some similarities first and
not this? Well, I think the first

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conditional you need to apply is the
one that you think will have more

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occurrences so if you think that most of
the users will enter the correct word,

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then you need to check for that
conditional first. You don't want the

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program to go through the conditionals
that have less probability to happen so

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you first want to go through this and
then the others are ignored

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if this returns to true. If this
doesn't return to true, if it's false,

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then you want to check for another
conditional. And when you when you check

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for more than two conditionals you need
to implement the elif statement.

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So for multiple conditionals and so we
need to, basically we need to check

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whether this list is empty or not. So if
it's not empty that means we got a match

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in the dictionary. In that case we want to
suggest that match, we want to mention

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that match in the message so which
means that if get close, sorry! Let me import

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it first. From difflib import
get_close_matches, so elif get_close_

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matches with the word given in data.keys.
Like that. So this is a list object,

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right? That's the same thing as this on here.
So this is a list object and you want to

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check whether the length, len, the length of
that list is greater than 0. It is you

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want return a message. Let's say did you
mean? We use a string formatter here %s.

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I'll explain what that is.
Instead. Did you mean that instead?

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An after the string, after you have closed
the quotes, use the percentage operator and here

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you pass the variable that will replace
this formatter inside this string,

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so this will be replaced with whatever
variable you pass on the right to this here.

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In our case we want to pass get_close_
matches for W and data.keys and you

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want to get
the first element of that list and put

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it here. So this is to understand it.
Let's say we have a variable which has

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a value of one and you say: �hey %s� like that
and percentage a and the percentage s

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will be replaced with one. That's the
same what we're doing in here. And yeah,

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that's all we have to do. Else,
so if this evaluates to false,

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and this evaluates to false as well, then
what that means is we are dealing with

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an empty list. So the user entered a
world that didn't have any match in our

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dictionary, didn't have any similar
words in our dictionary. So you want to

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return �the word doesn't exist�. Let me say
the script. Go to the terminal.

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The upper arrow key to call a previously
executed a command. So python 3 app1.py.

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Execute, enter a word. Let me start
with a correct word. Rain and you get

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the definitions for rainn. Let me execute
again. Rainn with an extra n and yeah,

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we get this message: �Did you mean rain
instead?� So the %s was

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replaced with the first item of the list
returned by get_close_matches and again

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if there's a very random string there
It says the word doesn't exist. Please

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double check it. And yeah that's it.
However I still see an issue with

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this, so we still can make the program
more user friendly. The problem now is that

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when the user enters like rainn by
mistake what you say you just pass a

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message there saying: �Did you
mean the rain instead?� �Oh yes, I mean

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rain, but how can I enter rain? Why do I
have to exit the program again?� So I'm

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thinking of a solution where instead of
just passing a message here and ending

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the program, instead of that you execute
another input statement so another input

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statement and another input function like
this one in here where you ask

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the users to enter let's say Y if they
meant rain or N for no. So Y for yes,

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N for no, if they didn't mean rain.
So if yes, then you basically you pass, you

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return the value for the rain word. If you
pass no to the input message, then you

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say sorry if they say that's not the
word that you meant that we don't know

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what you have in mind, so we say:
�The word doesn't exist. Please double-check

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it�. That's what I'm thinking, and yeah
think about this and I'm going to

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implement it see the next lecture.
Talk to you there.