/usr/lib/mysql-testsuite/t/1st.test is in percona-xtradb-cluster-testsuite-5.5 5.5.34-25.9+dfsg-0ubuntu4.
This file is owned by root:root, with mode 0o644.
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1 2 3 4 5 | #
# Check that we haven't any strange new tables or databases
#
show databases;
show tables in mysql;
|