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: stmt.rs
    path of file: ./repos/diesel/diesel/src/sqlite/connection
    
    the code of the file until where you have to start completion: #![allow(unsafe_code)] // fii code
use super::bind_collector::{InternalSqliteBin
    
    unsafe fn column_name(&self, idx: i32) -> *const str {
        let name = {
            let column_name =
                ffi::sqlite3_column_name(self.statement.statement.inner_statement.as_ptr(), idx);
            assert!(
                !column_name.is_null(),
                "The Sqlite documentation states that it only returns a \
                 null pointer here if we are in a OOM condition."
            );
            CStr::from_ptr(column_name)
        };
        name.to_str().expect(
            "The Sqlite documentation states that this is UTF8. \
             If you see this error message something has gone \
             horribly wrong. Please open an issue at the \
             diesel repository.",
        ) as *const str
    }