Syntax for constraining an associated type in a generic trait impl

associated_type_constraint.rs

trait Connection;

trait ManageConnection {
    type Connection;
    type Error;
}

struct ConnectionManager;
struct Error;

/// Associated type `Connection` should be any type that implements the `Connection` trait.
impl<C> ManageConnection for ConnectionManager where ??? {
    type Connection = C;
    type Error = Error;
}