Then, we load the module into the current session (import-module ./mdl.psm1), use the functions incVar and decVar to modify the value of the internal variable and then print its value with the mentioned syntax:
set-strictMode -version latest
import-module ./mdl.psm1
incVar
incVar
incVar
decVar
& (get-module mdl) { write-host "value of variable is $private_variable" }