/usr/share/dh-rebar/template/pkg.install.in is in dh-rebar 0.0.4.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 | test -d @@REBAR_BIN_DIR@@ && echo usr/lib/erlang/lib/@@E_PKG_NAME@@-@@PKG_VERSION@@/ebin
test -d @@REBAR_LIB_DIR@@ && echo usr/lib/erlang/lib/@@E_PKG_NAME@@-@@PKG_VERSION@@/priv
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