apt-get build-dep python3

notes.txt

The following NEW packages will be installed:
  autotools-dev bsdmainutils debhelper debiandoc-sgml dh-python
  dh-strip-nondeterminism distro-info-data docutils-common file gettext
  gettext-base groff-base intltool-debian libarchive-zip-perl libasprintf0v5
  libcroco3 libexpat1 libffi6 libfile-stripnondeterminism-perl libglib2.0-0
  libhtml-parser-perl libhtml-tagset-perl libicu55 libmagic1 libmpdec2 libosp5
  libpipeline1 libpython3-stdlib libpython3.5-minimal libpython3.5-stdlib
  libroman-perl libsgmls-perl libsqlite3-0 libtext-format-perl
  libtimedate-perl libunistring0 liburi-perl libxml2 lsb-release man-db
  mime-support opensp po-debconf python3 python3-docutils python3-minimal
  python3-roman python3.5 python3.5-minimal sgml-base sgml-data sgmlspl
  xml-core