Say Mussorgsky introducing himself is shameless (8)

I believe the answer is:

immodest

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'shameless' is the definition.
(I've seen this before)

I cannot understand how the remainder of the clue works.

(Other definitions for immodest that I've seen before include "Cheeky" , "Offending against sexual mores in appearance" , "Swift proposal was not" , "Conceited or indecent" , "Improper" .)

I've seen this clue in The Independent.

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