Can't locate namespace/autoclean.pm in @INC

[wangxinyu0922]

Hi, I want to try the perl script enhanced_collapse_empty_nodes.pl with the following command:
perl enhanced_collapse_empty_nodes.pl ../train-dev/UD_English-EWT/en_ewt-ud-train.conllu > en_ewt-ud-train-collapsed.conllu
But I get the following error:

Can't locate namespace/autoclean.pm in @INC (you may need to install the namespace::autoclean module) (@INC contains: /home/wangxy/workspace/iwpt2020/tools /etc/perl /usr/local/lib/x86_64-linux-gnu/perl/5.26.1 /usr/local/share/perl/5.26.1 /usr/lib/x86_64-linux-gnu/perl5/5.26 /usr/share/perl5 /usr/lib/x86_64-linux-gnu/perl/5.26 /usr/share/perl/5.26 /usr/local/lib/site_perl /usr/lib/x86_64-linux-gnu/perl-base) at /home/wangxy/workspace/iwpt2020/tools/Graph.pm line 4.
BEGIN failed--compilation aborted at /home/wangxy/workspace/iwpt2020/tools/Graph.pm line 4.
Compilation failed in require at enhanced_collapse_empty_nodes.pl line 38.
BEGIN failed--compilation aborted at enhanced_collapse_empty_nodes.pl line 38.

Any suggestion for this? Thank you.

[wangxinyu0922]

solved