Error: 'deb [arch=amd64] https://download.docker.com/linux/ubuntu xenial stable' invalid

Error: ‘deb [arch=amd64] https://download.docker.com/linux/ubuntu xenial stable’ invalid (2 Solutions!)

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With thanks & praise to God, and with thanks to the many people who have made this project possible! | Content (except music & images) licensed under cc by-sa 3.0 | Music: https://www.bensound.com/royalty-free-music | Images: https://stocksnap.io/license & others | With thanks to user wjandrea (https://askubuntu.com/users/301745), user Redscarfs (https://askubuntu.com/users/775847), user ravery (https://askubuntu.com/users/694267), user David Foerster (https://askubuntu.com/users/175814), and the Stack Exchange Network (http://askubuntu.com/questions/989881). Trademarks are property of their respective owners. Disclaimer: All information is provided “AS IS” without warranty of any kind. You are responsible for your own actions. Please contact me if anything is amiss at Roel D.OT VandePaar A.T gmail.com.

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