Sort packages by size one-liner as function

While surfing web I've discovered nice one-liner that suits my need well

expac -s "%-30n %m" | sort -hk 2 | awk '{print $1, $2/1024/1024}' | column -t|

However all the functional needed I got used to wrap in functions and there is problem in making function from this one-liner.

So I tried to insert this into my .bashrc file:

size()
{
    expac -s "%-30n %m" | sort -hk 2 | awk '{print $1, $2/1024/1024}' | column -t
}

and got this error:

[user@srv ~]$ size: a.out: No such file

So my question is: what's wrong about this function and how to fix it?