cut(1) -d%3A -f 1-3%2C1 %2Fetc%2Fpasswd %7C head -1
remove sections from each line of files
-d, --delimiter=DELIM
       use DELIM instead of TAB for field delimiter
-f, --fields=LIST
       select only these fields;  also print any line that contains no delimiter character, unless the -s
       option is specified
With no FILE, or when FILE is -, read standard input.
source manpages: cut