pool problems

   Compiling pool_problems v0.1.0 (file:///home/user/bbatha/experiments/pool_problems)
src/executor.rs:70:55: 70:61 error: cannot infer an appropriate lifetime for automatic coercion due to conflicting requirements [E0495]
src/executor.rs:70             let executor = Executor::new(auth_method, &scope);
                                                                         ^~~~~~
src/executor.rs:69:9: 73:11 note: first, the lifetime cannot outlive the method call at 69:8...
src/executor.rs:69         pool.scoped(|scope| {
src/executor.rs:70             let executor = Executor::new(auth_method, &scope);
src/executor.rs:71             let result = executor.execute(&"true", &host).recv().unwrap();
src/executor.rs:72             assert!(result.is_ok(), "Ensure you have a valid ssh-key pair for localhost");
src/executor.rs:73         });
src/executor.rs:69:9: 73:11 note: ...so that a type/lifetime parameter is in scope here
src/executor.rs:69         pool.scoped(|scope| {
src/executor.rs:70             let executor = Executor::new(auth_method, &scope);
src/executor.rs:71             let result = executor.execute(&"true", &host).recv().unwrap();
src/executor.rs:72             assert!(result.is_ok(), "Ensure you have a valid ssh-key pair for localhost");
src/executor.rs:73         });
src/executor.rs:69:29: 73:10 note: but, the lifetime must be valid for the anonymous lifetime #1 defined on the block at 69:28...
src/executor.rs:69         pool.scoped(|scope| {
src/executor.rs:70             let executor = Executor::new(auth_method, &scope);
src/executor.rs:71             let result = executor.execute(&"true", &host).recv().unwrap();
src/executor.rs:72             assert!(result.is_ok(), "Ensure you have a valid ssh-key pair for localhost");
src/executor.rs:73         });
src/executor.rs:69:27: 69:28 note: ...so that the reference type `&scoped_threadpool::Scope<'_, '_>` does not outlive the data it points at
src/executor.rs:69         pool.scoped(|scope| {
                                             ^
error: aborting due to previous error
Could not compile `pool_problems`.

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