Qualxuno potrebbe cortesemente dirmi cosa è che non va nel formato di
questo 'preferences'?
---- /etc/apt/preferences
# Explanation: Uninstall or do not install any Debian-originated
# Explanation: package versions other than the following
Package: *
Pin: release stretch
Pin-Priority 900
Package: *
Pin: release stretch-backports
Pin-Priority 950
Package: udev
Pin: version 236_3*
Pin-Priority: 1001
Package: libudev1
Pin: version 236_3*
Pin-Priority: 1001
Package: libudev-dev
Pin: version 236_3*
Pin-Priority: 1001
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