Malformed entry 55 in list file /etc/apt/sources.list ([option] no value)

root@ubuntu:~# sudo -E apt-get -y install apt-transport-https ca-certificates software-properties-common
E: Malformed entry 55 in list file /etc/apt/sources.list ([option] no value)
E: The list of sources could not be read.
E: Malformed entry 55 in list file /etc/apt/sources.list ([option] no value)
E: The list of sources could not be read.

vi /etc/apt/sources.list +55
## your rights to use the software. Also, please

deb [arch=] https://download.docker.com/linux/ubuntu bionic stable

deb [arch=arm64] https://download.docker.com/linux/ubuntu bionic stable