Use of uninitialized value in concatenation (.) or string at ./data line 9, <DATA> chunk <number of data line>.

##</code><code>##

cn: 
gid: 
members:

##</code><code>##

cn: username
gid: 102
members:

##</code><code>##

if(/^dn: cn/) {  # skip irrelevant paragraphs