You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: lib.rs
    path of file: ./repos/pgrx/pgrx/src
    
    the code of the file until where you have to start completion: //LICENSE Portions Copyright 2019-2021 ZomboDB, LLC.
//LICENSE
//LICENSE Portions Copyright 2021-2023 Technology Concepts & Design, Inc.
//LICENSE
//LICENSE Portions Copyright 2023-2023
    
        pub extern "C" fn Pg_magic_func() -> &'static ::pgrx::pg_sys::Pg_magic_struct {
            static MY_MAGIC: ::pgrx::pg_sys::Pg_magic_struct = ::pgrx::pg_sys::Pg_magic_struct {
                len: ::core::mem::size_of::<::pgrx::pg_sys::Pg_magic_struct>() as i32,
                version: ::pgrx::pg_sys::PG_VERSION_NUM as i32 / 100,
                funcmaxargs: ::pgrx::pg_sys::FUNC_MAX_ARGS as i32,
                indexmaxkeys: ::pgrx::pg_sys::INDEX_MAX_KEYS as i32,
                namedatalen: ::pgrx::pg_sys::NAMEDATALEN as i32,
                #[cfg(feature = "pg12")]
                float4byval: ::pgrx::pg_sys::USE_FLOAT4_BYVAL as i32,
                float8byval: cfg!(target_pointer_width = "64") as i32,
                #[cfg(any(feature = "pg15", feature = "pg16"))]
                abi_extra: {
                    // we'll use what the bindings tell us, but if it ain't "PostgreSQL" then we'll
                    // raise a compilation error unless the `unsafe-postgres` feature is set
                    let magic = ::pgrx::pg_sys::FMGR_ABI_EXTRA;
                    let mut abi = [0 as ::pgrx::ffi::c_char; 32];
                    let mut i = 0;
                    while i < magic.len() {
                        abi[i] = magic[i] as _;
                        i += 1;
                    }
                    abi
                },
            };

            // since Postgres calls this first, register our panic handler now
            // so we don't unwind into C / Postgres
            ::pgrx::pg_sys::panic::register_pg_guard_panic_hook();

            // return the magic
            &MY_MAGIC
        }