Format municipio codes with leading zeroes
Examples
# Format the concatenated string of state code + municipio code
str_mxmunicipio(c("1006", "2003"))
#> [1] "01006" "02003"
# Format the state and municipio code separately
str_mxmunicipio(c(10, 6), c(20, 3))
#> [1] "10020" "06003"
if (FALSE) { # \dontrun{
# warning about invalid code
str_mxmunicipio(33, 999)
} # }