The module is used to create/maintain user accounts from a text file
(usually produce by another database).
The module can parse a text file and extract fields (userid, gecos,
password,...) in various position on text line. It can now combine
and format them. For example, if you have some numeric ID referencing
a user, you can prefix it with a letter: a#2 will put a a prefix in front
of the second field of the line.
It can also be used to combine two fields. For example, you may have
the name and the surname as different fields in the input file
and used them to setup the gecos field.