Magento 2.0.18 is the final 2.0.x release. After March 2018, Magento 2.0.x will no longer receive security patches, quality fixes, or documentation updates.
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Cannot clone the Magento GitHub repository


Error is similar to the following:

Cloning into 'magento2'...
Permission denied (publickey).
fatal: The remote end hung up unexpectedly


Upload your SSH key to GitHub as discussed in the GitHub help page.