# File lib/rudy/aws/ec2/instance.rb, line 163
163:       def list_group(group=nil, state=nil, inst_ids=[], &each_inst)
164:         instances = list_group_as_hash(group, state, inst_ids, &each_inst)
165:         instances &&= instances.values
166:         instances = nil if instances && instances.empty? # Don't return an empty hash
167:         instances
168:       end