command:
echo LANG=en_US.UTF-8 >> /etc/locale.conf
echo LC_ALL=en_US.UTF-8 >> /etc/locale.conf
export LANGUAGE=en_US.UTF-8
export LANG=en_US.UTF-8
export LC_ALL=en_US.UTF-8
locale-gen en_US en_US.UTF-8
locale-gen fr_FR.utf8
dpkg-reconfigure locales

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