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+# Add new apt source:
+### Location
+/etc/apt/sources.list.d/
+
+#### Example content:
+deb http://ddebs.ubuntu.com ${VERSION_CODENAME} main restricted universe multiverse
+deb http://ddebs.ubuntu.com ${VERSION_CODENAME}-updates main restricted universe multiverse
+deb http://ddebs.ubuntu.com ${VERSION_CODENAME}-proposed main restricted universe multiverse
+
+
+### Add the public key
+sudo apt-key adv --keyserver keyserver.ubuntu.com --recv-keys 
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