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Key Sequence Detection (Konami Code)

If we take a look at Wikipedia:

The Konami Code was created by Kazuhisa Hashimoto, who was developing the home port of the 1985 arcade game Gradius, a scrolling shooter released on the NES in 1986. Finding the game too difficult to play through during testing, he created a cheat code to give the player a full set of power-ups (normally attained gradually throughout the game). After entering the sequence using the controller when the game was paused the player received all available power-ups. The mistake was discovered after the release, but developers decided to leave it there, as removing it could result in new bugs and glitches. The sequence was easy enough to remember for testers and simultaneously sufficiently hard to enter accidentally during the gameplay for unsuspecting users.
The code has been subsequently re-used in a large number of other games and a varied version of the code is now used in the Opera Browser to activate hidden advanced settings.

I have made a code on this page also for you to guess.