Software error:

Can't locate Digest/SHA1.pm in @INC (you may need to install the Digest::SHA1 module) (@INC contains: . /etc/perl /usr/local/lib/x86_64-linux-gnu/perl/5.34.0 /usr/local/share/perl/5.34.0 /usr/lib/x86_64-linux-gnu/perl5/5.34 /usr/share/perl5 /usr/lib/x86_64-linux-gnu/perl-base /usr/lib/x86_64-linux-gnu/perl/5.34 /usr/share/perl/5.34 /usr/local/lib/site_perl) at Core/Access.pm line 3.
BEGIN failed--compilation aborted at Core/Access.pm line 3.
Compilation failed in require at shepherd.cgi line 18.
BEGIN failed--compilation aborted at shepherd.cgi line 18.

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