It is possible to create entries within People based on a site's Users. This is done by exporting the list of users to a .CSV file, and then importing people from that .CSV file. It is important that you only do this once, as repeating this process will add 2nd, 3rd, and more copies of each person into your 'people' content area. However, it can be incredibly useful when migrating from User Profiles.
Export Users to CSV
Go to Tools > Import/Export Users and select the green Export Users button. Download the generated .CSV file to your computer.
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