[...]
Package files:
 100 /var/lib/dpkg/status
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 100 http://us.archive.ubuntu.com/ubuntu xenial-backports/universe i386 Packages
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 100 http://us.archive.ubuntu.com/ubuntu xenial-backports/universe amd64 Packages
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 100 http://us.archive.ubuntu.com/ubuntu xenial-backports/main amd64 Packages
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 500 http://us.archive.ubuntu.com/ubuntu xenial-updates/multiverse amd64 Packages
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 500 http://us.archive.ubuntu.com/ubuntu xenial-updates/universe i386 Packages
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 500 http://us.archive.ubuntu.com/ubuntu xenial-updates/universe amd64 Packages
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 500 http://us.archive.ubuntu.com/ubuntu xenial-updates/main i386 Packages
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 500 http://us.archive.ubuntu.com/ubuntu xenial-updates/main amd64 Packages
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 500 http://us.archive.ubuntu.com/ubuntu xenial/multiverse i386 Packages
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 500 http://us.archive.ubuntu.com/ubuntu xenial/multiverse amd64 Packages
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 500 http://us.archive.ubuntu.com/ubuntu xenial/universe i386 Packages
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 500 http://us.archive.ubuntu.com/ubuntu xenial/universe amd64 Packages
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 500 http://us.archive.ubuntu.com/ubuntu xenial/restricted amd64 Packages
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 500 http://us.archive.ubuntu.com/ubuntu xenial/main i386 Packages
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 500 http://us.archive.ubuntu.com/ubuntu xenial/main amd64 Packages
     release v=16.04,o=Ubuntu,a=xenial,n=xenial,l=Ubuntu,c=main,b=amd64
     origin us.archive.ubuntu.com
Pinned packages: