Installing libc*-pp-gcc* packages for prettyprinters in gdb.
Does not configure gdb to load the prettyprinters by default.

Have to add lines to ~/.gdbinit file.

% cat ~/.gdbinit 
python
import sys
sys.path.insert(0, '/usr/share/gcc-9/python')
from libstdcxx.v6.printers import register_libstdcxx_printers
register_libstdcxx_printers (None)
end
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