One micrometer equals $1000$ nanometers. The following program intends to read a floating$-$point value from input, convert the value from nanometers to micrometers, and output the length in micrometers, but the code contains an error. Find and fix the error.

Ex: If the input is $3\mathrm{.}7,$ then the output is:

$0\mathrm{.}004$ micrometers

$12345$

# Modify the following codelength$\_$nano $=$ int$($input$())$length$\_$micro $=$ length$\_$nano $/1000$print$($f$\text{'}\{$length$\_$micro:$\mathrm{.}3$f$\}$ micrometers'$)$