/bin/autopartition-lvm is in ubiquity 18.04.14.
This file is owned by root:root, with mode 0o755.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 | #!/bin/sh
. /lib/partman/lib/auto-lvm.sh
devs="$*"
method="lvm"
auto_lvm_prepare "$devs" $method || exit $?
auto_lvm_perform || exit 1
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