/usr/share/nano/mgp.nanorc is in nano 2.7.4-1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 | ## Here is an example for Magicpoint presentations.
syntax "mgp" "\.mgp$"
header "^%include.*"
comment "#"
icolor green "^%[a-z].*$"
color cyan "(^|[[:space:]])#.*$"
color cyan "(^|[[:space:]])%%.*$"
color ,green "[[:space:]]+$"
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