Question rust returning a reference to a integer from a function was tagged as duplicate, and almost is.

The question Why can I return a reference to a local literal but not a variable? was referenced, suggesting that &42 were static.
However, code (playground)

use std::ops::Deref;

struct Curse<T>(T);

impl<T> Deref for Curse<T> {
    type Target = usize;
    
    fn deref(&self) -> &<Self as Deref>::Target {
        &42 // wat
    }
   
}

fn main() {
    let a = 123;
    let c = *{
        let b = Curse(a);
        b.deref()
    };
    
    println!("{a} {c}");
}

will result in:

Exited with status 101

Standard Error

   Compiling playground v0.0.1 (/playground)
error[E0597]: `b` does not live long enough
  --> src/main.rs:18:9
   |
17 |         let b = Curse(a);
   |             - binding `b` declared here
18 |         b.deref()
   |         ^ borrowed value does not live long enough
19 |     };
   |     - `b` dropped here while still borrowed

For more information about this error, try `rustc --explain E0597`.
error: could not compile `playground` (bin "playground") due to 1 previous error

Standard Output

So, in this case, the lifetime seems conditionned by the lifetime of &self