исходный пакет докера

Я пытаюсь загрузить исходные пакеты Docker в Ubuntu 19.04, но apt-get update завершается с ошибкой:

: Skipping acquire of configured file 'stable/source/Sources' as repository 'https://download.docker.com/linux/ubuntu disco InRelease' does not seem to provide it (sources.list entry misspelt?)
root@kallol-OptiPlex-9020:~#

Файл /etc/apt/sources.list:

# This system was installed using small removable media
# (e.g. netinst, live or single CD). The matching "deb cdrom"
# entries were disabled at the end of the installation process.
# For information about how to configure apt package sources,
deb [arch=amd64] https://download.docker.com/linux/ubuntu disco stable
deb-src [arch=amd64] https://download.docker.com/linux/ubuntu disco stable
# see the sources.list(5) manual.
root@kallol-OptiPlex-9020:~# 

Любая идея ?

Альтернатива, можно ли загрузить пакет urntu docker src вручную?