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: utils.rs
    path of file: ./repos/qdrant/lib/segment/src/common
    
    the code of the file until where you have to start completion: use std::collections::HashMap;
use std::ops::Bound;

use serde_json::Value;
use smallvec::{smallvec, SmallVec};

use crate::data_types::named_vectors::NamedVectors;
use crate::data_types::vectors::Vector;
use crate::index::field_index::FieldIndex;
use crate::json_path::JsonPathString;
use crate::types::PayloadKeyType;

pub type IndexesMap = HashMap<PayloadKeyType, Vec<FieldIndex>>;

/// A container for JSON values, optimized for the common case of a single value.
pub type MultiValue<T> = SmallVec<[T; 1]>;

pub fn check_is_empty<'a>(values: impl IntoIterator<Item = &'a Value>) -> bool {
    v
    
    fn test_is_empty<P: JsonPathInterface>() {
        let map = serde_json::from_str::<serde_json::Map<String, Value>>(
            r#"
                {
                   "a": [
                     { "b": 1 },
                     { "b": 2 },
                     { "b": null },
                     { "d": [] },
                     { "d": [] },
                     { "f": null }
                   ]
                }
            "#,
        )
        .unwrap();
        let multivalue = path::<P>("a[].b").value_get(&map);
        let is_empty = check_is_empty(multivalue.iter().copied());

        assert!(!is_empty, "a[].b is not empty");

        let multivalue = path::<P>("a[].c").value_get(&map);
        let is_empty = check_is_empty(multivalue.iter().copied());

        assert!(is_empty, "a[].c is empty");

        let multivalue = path::<P>("a[].d").value_get(&map);
        let is_empty = check_is_empty(multivalue.iter().copied());
        assert!(is_empty, "a[].d is empty");

        let multivalue = path::<P>("a[].f").value_get(&map);
        let is_empty = check_is_empty(multivalue.iter().copied());
        assert!(is_empty, "a[].f is empty");
    }