Where is the script below from?

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ARTHUR: O Knights of Ni, we have brought you your shrubbery. May we go now?

HEAD KNIGHT: It is a good shrubbery. I like the laurels particularly,... but there is one small problem.

ARTHUR: What is that?

HEAD KNIGHT: We are now... no longer the Knights Who Say 'Ni'.

KNIGHTS OF NI: Ni! Shh!

HEAD KNIGHT: Shh! We are now the Knights Who Say 'Ecky-ecky-ecky-ecky-pikang-zoop-boing-goodem-zu-owly-zhiv'.

RANDOM: Ni!

HEAD KNIGHT: Therefore, we must give you a test.

ARTHUR: What is this test, O Knights of-- knights who till recently said 'ni'?

HEAD KNIGHT: Firstly, you must find... another shrubbery!

[dramatic chord]

ARTHUR: Not another shrubbery!

RANDOM: Ni!

HEAD KNIGHT: Then, when you have found the shrubbery, you must place it here beside this shrubbery, only slightly higher so you get the two-level effect with a little path running down the middle.

KNIGHTS OF NI: A path! A path! A path! Ni! Shh! Knights of Ni! Ni! Ni! Shh! Shh!...

HEAD KNIGHT: Then, when you have found the shrubbery, you must cut down the mightiest tree in the forest... with... a herring!

[dramatic chord]

KNIGHTS OF NI: A herring!

ARTHUR: We shall do no such thing!

HEAD KNIGHT: Oh, please!

ARTHUR: Cut down a tree with a herring? It can't be done.

KNIGHTS OF NI: Aaaaugh! Aaaugh!

HEAD KNIGHT: Augh! Ohh! Don't say that word.

ARTHUR: What word?

HEAD KNIGHT: I cannot tell, suffice to say is one of the words the Knights of Ni cannot hear.

ARTHUR: How can we not say the word if you don't tell us what it is?

KNIGHTS OF NI: Aaaaugh!

HEAD KNIGHT: You said it again!

ARTHUR: What, 'is'?

KNIGHTS OF NI: Agh! No, not 'is'.

HEAD KNIGHT: No, not 'is'. You wouldn't get vary far in life not saying 'is'.

KNIGHTS OF NI: No, not 'is'. Not 'is'.

BEDEVERE: My liege, it's Sir Robin!
The script appears to be from 'Monty Python and the Holy Grail', which is a British comedy film directed by Terry Gilliam and Terry Jones and performed by the Monty Python comedy group. It parodies the legend of King Arthur's quest to find the Holy Grail and is known for it's slapstick humor.
Correct! What are some of the other notable scenes from this movie? List a few with short summaries.