Let's start by creating a new file in our workspace called app.py.

For our example here, I'll define the symbol method that just prints a little

hello statement from our app.

And then call the method to print that statement.

We'll print

Hello from app.

Save our file.

Go to the Console.

And when we run our app, as expected, we get our output., great.

Let's create a second file, we'll call it second_app.py.

In here, we'll import app, And

then we'll add another short print statement, Well, from second app.

We can save that, And run it.

Let's see what happens now with that import.

Well, that's not entirely what we want.

We really don't want to be calling print hello just by importing app.py.

This is where we can utilize that conditional check with dunder name.

Let's head back into app.py and add that.

So right above our print_hello call, We'll add,

if __name__, == __main__.

Come over here, indent.

Now Python will check to see if app.py is the main module being run, or

if it is being imported.

Let's double check this from the command line to make sure

things are working as we have intended.

We run python app.py again.

Nice, that still works.

And if we run second_app.py,

That's better.

And since we've imported app.py into second_app.py,

we can call our print hello function when and if we need it.

App_print_hello,

Save it.

Let's clear our console here, And run second_app.py again.

Great, so we have access to print hello from our second app.

Let's take a quick peek at dunder name by adding another print statement to app.py.

Well print __name.

Now, when we run our scripts, we can see the value of dunder name,

based on if the module is run directly or imported.

We'll run app.py and see dunder_name is equal to dunder_main.

And if we run second_app.py, We see that dunder_name is equal to app.

Notice here as well that by having the print dunder_name statement in app.py

outside of a function, that command is run first inside second_app.py.

This is another important reason to have statements inside methods or

inside a conditional check for dunder name when using imports.

Along your journey as a Pythonista, you'll find many recommended best practices.

This conditional check is a common part of most Python programs and

is used in all sorts of Python applications

from trade Python scripts to Python frameworks like Flask and Django.

With this best practice in place, you can provide for

better management with what is happening in your scripts.

I look forward to seeing what you build.

Until next time, happy coding.