Where to put an email function

[eluser]CARP[/eluser]
Hi guys
I have built an app for government that allow users to request a new e-mail address account related to government.
This CI app sends mail notifications to mail server admins when a new user requests an account.

I have this code cloned in some controllers

Code:

$this->load->library('email');            
    $this->email->from('[email protected]', 'Acc. req. system');
    $this->email->to('[email protected]');
    $this->email->cc('[email protected]');
    $this->email->bcc('[email protected]');
    $this->email->subject('[EMAIL] New request');
    $this->email->message('blabla');
    $this->email->send();
    //echo $this->email->print_debugger();

I'd like to build a function somewhere with some parameters for sending mails, for example:

Code:

send_email($to, $from, $cc, $bcc, $message);

Where should I build this function? Inside a controller? How should then I call it from another or the same controller?

Thanks a lot in advance. Hope you've understood my question.