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Slide 1

"Names" in Python

Let's Learn
Some More
[Python]
[Programming]


Slide 2

We Will Review Some
[Fundamental Concepts]
In Python Programming
Using Python REPL.

Here's Another Simple
Python Program:

^^^ secret = 42
^^^ secret


Slide 3

What is a "Name" in a Program?
A Name is Used to Refer to
An "Object" in Python.
We Already Saw One Example, `_`.

^^^ Secret = 42

This "Assignment Statement"
Create a (New) Name `Secret`
In the Python Program,
And, it "Binds" the Name
To the "Object" `42`.


Slide 4

So, What Does This Do?

^^^ Secret

Referring to a Name is Also
An Expression in Python.
It "Evaluates" the Name
By Returning the "Value" of
The "Object" that it Refers to.
In this example,
the Name `secret`
Refers to the Object `42`. Hence,

^^^ Secret
42


Slide 5

Referring to a ["Bad Name"]
Will Result in an Error.
There are Possibly Two Different Causes:

A Name Exists But Refers to Nothing, And
A Name Simply Does Not Exist.

In Python, The Second Error is
A Much More Common Scenario.
In General, In Python,
You Cannot Create a Name
Without Having an Object
That it Refers to!


Slide 6

Learn [Python] Programming
For 60 Seconds a Day!
See You All in the Next Lesson!