Macro get_trampoline_function 

#[doc(hidden)]
macro_rules! get_trampoline_function {
    ($trampoline:ident, $f:path) => { ... };
}

Generates an implementation of MethodDef and then returns the trampoline function specialized to call the provided method.

Note that the functions returned by this macro are instantiations of generic functions. Code should not depend on these function pointers being stable (e.g. across compilation units); the intended purpose of these is to create function pointers which can be passed to the Python C-API to correctly wrap Rust functions.