升级到 ubuntu 20.04 后，一些软件包仍保留在 +bionic1 版本中
sudo apt list | grep python3.8
WARNING: apt does not have a stable CLI interface. Use with caution in scripts.
idle-python3.8/focal-updates,focal-updates,focal-security,focal-security 3.8.2-1ubuntu1.1 all
libpython3.8-dbg/focal-updates,focal-security 3.8.2-1ubuntu1.1 amd64
libpython3.8-dbg/focal-updates,focal-security 3.8.2-1ubuntu1.1 i386
libpython3.8-dev/focal-updates,focal-security 3.8.2-1ubuntu1.1 amd64
libpython3.8-dev/focal-updates,focal-security 3.8.2-1ubuntu1.1 i386
libpython3.8-minimal/now 3.8.2-1+bionic1 amd64 [installed,local]
libpython3.8-minimal/focal-updates,focal-security 3.8.2-1ubuntu1.1 i386
libpython3.8-stdlib/now 3.8.2-1+bionic1 amd64 [installed,local]
libpython3.8-stdlib/focal-updates,focal-security 3.8.2-1ubuntu1.1 i386
libpython3.8-testsuite/focal-updates,focal-updates,focal-security,focal-security 3.8.2-1ubuntu1.1 all
libpython3.8/focal-updates,focal-security 3.8.2-1ubuntu1.1 amd64
libpython3.8/focal-updates,focal-security 3.8.2-1ubuntu1.1 i386
python3.8-dbg/focal-updates,focal-security 3.8.2-1ubuntu1.1 amd64
python3.8-dbg/focal-updates,focal-security 3.8.2-1ubuntu1.1 i386
python3.8-dev/focal-updates,focal-security 3.8.2-1ubuntu1.1 amd64
python3.8-dev/focal-updates,focal-security 3.8.2-1ubuntu1.1 i386
python3.8-doc/focal-updates,focal-updates,focal-security,focal-security 3.8.2-1ubuntu1.1 all
python3.8-examples/focal-updates,focal-updates,focal-security,focal-security …