rust/src/librustc_error_codes/error_codes/E0432.md

An import was unresolved.

Erroneous code example:

use something::Foo; // error: unresolved import `something::Foo`.

Paths in use statements are relative to the crate root. To import items relative to the current and parent modules, use the self:: and super:: prefixes, respectively. Also verify that you didn't misspell the import name and that the import exists in the module from where you tried to import it. Example:

use self::something::Foo; // ok!

mod something {
    pub struct Foo;
}
# fn main() {}

Or, if you tried to use a module from an external crate, you may have missed the extern crate declaration (which is usually placed in the crate root):

extern crate core; // Required to use the `core` crate

use core::any;
# fn main() {}