Note, selecting 'clang-tidy-4.0' for regex 'Clang+'
Note, selecting 'python-clang-5.0' instead of 'python-clang-x.y'
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:

The following packages have unmet dependencies:
python-clang-3.5 : Breaks: python-clang-3.6 but 1:3.6.2-3ubuntu2 is to be installed
                Breaks: python-clang-3.7 but 1:3.7.1-2ubuntu2 is to be installed
                Breaks: python-clang-3.8 but 1:3.8-2ubuntu4 is to be installed
python-clang-3.6 : Breaks: python-clang-3.5 but 1:3.5.2-3ubuntu1 is to be installed
                Breaks: python-clang-3.7 but 1:3.7.1-2ubuntu2 is to be installed
                Breaks: python-clang-3.8 but 1:3.8-2ubuntu4 is to be installed
python-clang-3.7 : Breaks: python-clang-3.5 but 1:3.5.2-3ubuntu1 is to be installed
                Breaks: python-clang-3.6 but 1:3.6.2-3ubuntu2 is to be installed
                Breaks: python-clang-3.8 but 1:3.8-2ubuntu4 is to be installed
python-clang-3.8 : Breaks: python-clang-3.5 but 1:3.5.2-3ubuntu1 is to be installed
                Breaks: python-clang-3.6 but 1:3.6.2-3ubuntu2 is to be installed
                Breaks: python-clang-3.7 but 1:3.7.1-2ubuntu2 is to be installed
python-clang-3.9 : Breaks: python-clang-3.5 but 1:3.5.2-3ubuntu1 is to be installed
                Breaks: python-clang-3.6 but 1:3.6.2-3ubuntu2 is to be installed
                Breaks: python-clang-3.7 but 1:3.7.1-2ubuntu2 is to be installed
                Breaks: python-clang-3.8 but 1:3.8-2ubuntu4 is to be installed
python-clang-4.0 : Breaks: python-clang-3.5 but 1:3.5.2-3ubuntu1 is to be installed
                Breaks: python-clang-3.6 but 1:3.6.2-3ubuntu2 is to be installed
                Breaks: python-clang-3.7 but 1:3.7.1-2ubuntu2 is to be installed
                Breaks: python-clang-3.8 but 1:3.8-2ubuntu4 is to be installed
                Breaks: python-clang-3.9 but 1:3.9.1-4ubuntu3~16.04.2 is to be installed
python-clang-5.0 : Breaks: python-clang-3.5 but 1:3.5.2-3ubuntu1 is to be installed
                Breaks: python-clang-3.6 but 1:3.6.2-3ubuntu2 is to be installed
                Breaks: python-clang-3.7 but 1:3.7.1-2ubuntu2 is to be installed
                Breaks: python-clang-3.8 but 1:3.8-2ubuntu4 is to be installed
                Breaks: python-clang-3.9 but 1:3.9.1-4ubuntu3~16.04.2 is to be installed

$ sudo apt-get install --dry-run Clang++
Reading package lists... Done
Building dependency tree
Reading state information... Done
Note, selecting 'clang-modernize-5.0' for regex 'Clang+'
Note, selecting 'libclang-3.6-dev' for regex 'Clang+'
.
.
.
Note, selecting 'python-clang-3.3' for regex 'clang+'
Note, selecting 'python-clang-3.4' for regex 'clang+'
Note, selecting 'python-clang-3.5' for regex 'clang+'
Note, selecting 'python-clang-3.6' for regex 'clang+'
Note, selecting 'python-clang-3.7' for regex 'clang+'
Note, selecting 'python-clang-3.8' for regex 'clang+'
Note, selecting 'python-clang-3.9' for regex 'clang+'
.
.
.

sudo apt install clang