How to create a seperate helper function in Perl?

Hi,
I have a few Perl packages. In these packages, there is a piece of code that I repeat every time. Therefore, I would like to create a separate function (a separate function in a helperFunctions directory) and when I need that piece of code, I will call this function with certain inputs and return the output to the caller.

Example:

package xxx::yyy;
use strict;
use warnings;

sub yyy{

some code-1

some repetitve code-1
some repetitve code-2
some repetitve code-3
some repetitve code-4
some repetitve code-5

some code-2

}
1;

I want this code to be like this:

package xxx::yyy;
use strict;
use warnings;

sub yyy{

some code-1

call helperFunction lineNumbers.pm here and return the output

some code-2

}
1;

How can I do it?

Can you send me a basic hello world example?

the directory structure is like this:

/dir1/yyy.pm

The helperFunctions dir will be like this:

/dir1/helperFunctions/lineNumbers.pm