Hello,

I am facing an issue by following http://wiki.ros.org/melodic/Installation/Source

rosdep install --from-paths src --ignore-src --rosdistro melodic -y
WARNING: ROS_PYTHON_VERSION is unset. Defaulting to 2
executing command [sudo -H apt-get install -y python-rospkg-modules]
Lecture des listes de paquets... Fait
Construction de l'arbre des dépendances       
Lecture des informations d'état... Faitrosdep install --from-paths src --ignore-src --rosdistro melodic -y
WARNING: ROS_PYTHON_VERSION is unset. Defaulting to 2
executing command [sudo -H apt-get install -y python-rospkg-modules]
Lecture des listes de paquets... Fait
Construction de l'arbre des dépendances       
Lecture des informations d'état... Fait
E: Impossible de trouver le paquet python-rospkg-modules
ERROR: the following rosdeps failed to install
  apt: command [sudo -H apt-get install -y python-rospkg-modules] failed

E: Impossible de trouver le paquet python-rospkg-modules
ERROR: the following rosdeps failed to install
  apt: command [sudo -H apt-get install -y python-rospkg-modules] failed

I already tried :

sudo apt --fix-broken install
sudo apt-get install -y python-rospkg
sudo apt-get install -y python3-rospkg and sudo apt-get install -y python3-rospkg2

and this link : https://askubuntu.com/questions/1122642/stuck-in-the-loop-because-apt-fix-broken-install-doesnt-help-while-installi

Could you give to me some possible solution ?

Thx