How much time does it take to run this loop?

#how much time does it take to run this loop?

system.time$($for $($i in $1$:$1000)\{$i$+6\})$

#load package

library $($microbenchmark$)$

#how much time does it take to run this loop $($exactly$)?$

microbenchmark $($for $($i in $1$:$1000)\{$i$+6\})$