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- All right.

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so, let's go ahead now and
make a transition in code.

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- So much like our
transition from scratch to C

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and ultimately C to JavaScript.

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So with C to Python, I decided
to take the approach of trying

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to map one language to another.

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Give students a representative
example of a construct in C,

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whether it's a function, or a
loop, or condition, or a variable.

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And then show them
the equivalent Python.

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So much like in Scratch, they're
reassured that the idea is the same,

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but now you have a colon and you have
fewer parentheses and no semi-colon

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and you really have to indent.

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But it's not a big deal, is
the point at least, of that.

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And what I found hopefully was
helpful too in explaining this,

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or at least as helpful
for the way my mind works,

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is to actually pull up some
representative examples.

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Not just of lines of
code, but whole programs,

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and import them from C to Python.

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So that one, students ideally
already know how the C version works.

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So there's no cognitive barrier there.

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Now it's really just a syntactic
translation of one to the other.

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- So it's certainly nice then to have
that corpus of demos ready at hand.

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all of our lecturers come with
a zip of all of the source

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files that you show and lecture.

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And so we can just take those and
immediately transform them into Python.

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- And it's a very safe way, I
think, of exploring a new language.

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Even for me it was enlightening to just
take the C example and then figure out,

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all right here's the solution literally
on the left, how do we now on the right

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re-implement this in Python.

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And it's an opportunity
to read up on a language,

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figure out how I can do things
a little more elegantly,

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maybe Python really can tighten
some of those things up.

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Because you can you have some nice
constructs like for...in for instance.

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And so that was helpful
exercise I thought.

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- And super impactful is
the ability in CS50 IDE

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to actually have a split window
to show it literally side by side,

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as opposed to jumping back
and forth between them

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or showing them on a PowerPoint slide,
which is what we've done before.

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- I agree.

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And hopefully students found
this helpful too for pset 6.

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Since beyond the sentiment analysis
and the ML part of that problem

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set did we have students reimplement
Mario and/or Caesar or Visionaire

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or Crack, and so forth.

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And there too, I feel like
that's a very comfortable space

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to be in because, hey, you
already have your solution,

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whether it's yours or ours
that we made available.

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All you have to do is figure out now
how to map this to a new language

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and you have the entirety of Google
and the web at your disposal,

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as well as the lessons
learned from class.

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So hopefully that's a nice way
of sort of bootstrapping oneself

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to enough comfort to then bite off
something like sentiment analysis.

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- Now Python, as a language, has
much better I/O capabilities than C,

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at least out of the box.

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So what motivated, nonetheless,
we saw a little bit

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earlier porting the library to Python.

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- Yeah.

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It was a good question and it was
kind of a toss up because Python

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has a nice input function
that will just get you

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user input, much like getString.

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But I wanted to actually return
a specific data type, much

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like we did with C. And I also wanted
there to be really a one to one

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mapping for those early conversions,
those warm up exercises where

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you don't have to figure out how
getString and getInt and getFloat

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and so forth work.

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We actually want to just port those,
literally, over to the equivalence.

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Plus for some of our
teachers online, especially

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in CS50 AP who might be
using Python even more,

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it's just nice to be
able to hand students

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a library with which they can even
do earlier portions of the course,

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but in Python.

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So just having that in our
toolkit felt compelling,

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even though we very quickly
abandoned it deliberately

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for later in that same piece set.

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- I suppose even on its own it it allows
us to introduce the equivalent of pound

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include with Python's import.

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- Indeed.

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There's a nice mapping to that as well.

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