How to install opera?

[Peng Yu]

I have the latest ubuntu LTS. But I don't find opera. How to install opera?

http://www.opera.com/

$ sudo apt-get install opera
Reading package lists... Done
Building dependency tree
Reading state information... Done
Package opera is not available, but is referred to by another package.
This may mean that the package is missing, has been obsoleted, or
is only available from another source
E: Package opera has no installation candidate


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Regards,
Peng