Is there a way to automate fixing missing parens in Emacs? M-x fix-parens?

updated following Dirk's suggestion

After finding out about emacs' check-parens and show-parens modes in a previous question, the value of a fix-missing-parens mode, a开发者_开发百科 comment raised the point that it would be nice to automate the process of finding and adding missing or extra parens.

Is there a way to automate fixing such mismatched parens?

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Mark a region and call M-x indent-region -- that will indent the code which comprises parens (and more).