Vim: inserting at the end of the line

Is there a key to insert something at the end of the line in Vim? It would be similar to A, except it would insert before the last character, not after it.

A use case is for example in Python:

if ((a and b) or c:

and you want to insert the missing parenthesis before the colon. There are similar use cases in C-syntax languages when you want t开发者_StackOverflow中文版o insert something before the semi-colon.

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To insert before the last character, use $i. This isn't a common enough case to warrant a single-key command, apparently.

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There isn't a built-in command that uses one single keystroke, but If you use it often consider creating a map:

nnoremap Q $i

Alternatively you can use A<left> in your map to achieve the same effect.