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[MUSIC]

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When you give an app a model, it's likely
going to want a form for editing it.

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Django's admin automatically
creates forms for

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creating and editing instances of
our models once we register them.

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But what if we wanna do
it outside of the admin?

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Django provides us with a special
type of form known as a model form.

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A model form is basically
an automatically generated form

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based on a particular model.

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They provide a great easy way to
create new model instances and

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to edit existing ones.

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This means we get all of the goodness
of forms without having to write

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an entire form ourselves.

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So we have our models and we've already
looked at doing standard forms, but

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let's look at doing model forms.

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Model forms are forms that
are made off of our models.

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So we want to do this basically the same
way that we did our suggestion form.

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So that means we want to come here and
we want to add a new file named forms.py.

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And in forms.py, we of course want
to do from django import forms.

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So far, so
exactly the same as it was before.

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All right, so now we need to bring
in our models, so we'll say from.

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import models and now let's go ahead and
make our model forms.

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Let's make a quiz form first,

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this'll show pretty much all the stuff
that we're going to do with a model form.

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We'll say quiz form and
this is forms.modelform,

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thats the one difference right there,
or,the first one rather,

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is that we're going to do model
form instead of just form.

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And then we're not going to specify any
fields because we're just going to use

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the fields that the model gives us but
we're gonna have to specify a class meta.

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So in the class meta we
have specify two things,

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we have to specify the model
which is gonna be models.quiz,

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and then we have to specify fields and
so what fields does,

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there's two things here, and
I'll talk about both of them.

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So there's fields, which we specify
the fields that we want to include.

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So, for our quiz, we want to include
title, description, order, and

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total questions,
cuz those are always there.

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The opposite of this is exclude.

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And if we were doing this with
exclude instead of fields,

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let's come over here and
look at this quiz.

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So we have title, description,
order, course, and total questions.

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So, we might just say okay,
I'm going to exclude course.

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Because course is the one field
that I don't want to exclude.

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This isn't a great idea, and

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I'm gonna cover that in just a little
bit on why that's not a great idea.

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But just so you know that it's there.

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What it does is it basically
leaves off that field.

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That sounds like a great idea,
but there's a little gotcha.

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We'll talk about that in a minute.

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All right, so lets just do our fields and
our model right there.

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Lets go ahead and
actually make a couple more classes.

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Let's do a, I don't think we want
to do a question form because we're

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not going to answer, or we're not
going to create questions directly,

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we are going to create
true false questions.

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Or multiple choice questions.

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So let's create a TrueFalseQuestion form.

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And feel free to use shorter
names on these if you want.

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I tend to like really verbose names,
as you've probably noticed.

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So if you want something that's a little
bit more terse, feel free to do that.

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And we're going to do
TrueFalseQuestion as our model.

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And for fields we want to do order and

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prompt, cuz those are the only
questions we have for true false.

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Or the only options we have for
true false.

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We might want to change
our true false model.

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I'm not going to do it in the course but
you might want to change it so

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that you can just mark on the question
if it's true of if it's false.

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Totally up to you.

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And then for our last one we'll
do multiple choice question form.

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Oops, why did I put question form in here?

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It's not a question form.

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It's a model form.

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Forms.ModelForm.

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Just not thinking things through today.

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So, class Meta and again, model will be

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models.MultipleChoiceQuestion and

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our fields.

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We got a couple of extra fields.

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So we'll do order, prompt,
and shuffle answers.

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And there we go.

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So that is, that's our forms.

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And as you can probably see,

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there's not a whole lot of difference
between our model forms and

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the non-model forms that we created
earlier when we made the suggestion form.

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They're pretty similar,
the main difference is that we do

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this ModelForm thing and we do pretty
much all of our working class meadow.

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We don't specify the fields ourselves.

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Django will take our
fields from our models and

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turn them into the appropriate fields for
a form.

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So we don't have to worry about that
ourselves, which is really, really nice.

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I'm sure you can already see how model
forms save us a significant amount of work

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and coordination.

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We don't have to make sure
that our form fields and

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our model fields line up or,
anything like that.

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One thing that you might be tempted to do,
and I already talked about this a little,

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is to use exclude to leave off
fields that you don't want,

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instead of using fields to include
only the fields that you do want.

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This isn't the best idea though,

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because any field that's not listed in
exclude will be automatically included.

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So you add a new field to your model,
and bam!

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There it is in the form.

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By using the fields attribute,

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you keep your forms stable until you
explicitly add the new field to the list.

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And remember,
explicit is better than implicit.

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Okay, now that we have a couple
of model forms created,

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let's see about using them in our views.