usepercent_encoding::{NON_ALPHANUMERIC, utf8_percent_encode};usestd::path::{Path, PathBuf};/// create a distribution base directory
pubfndistribution_base(base: impl AsRef<Path>, url:&str)-> PathBuf{
base.as_ref().join(utf8_percent_encode(url,NON_ALPHANUMERIC).to_string())}