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: example.rs
    path of file: ./repos/cnosdb/query_server/query/src/extension/expr/aggregate_function
    
    the code of the file until where you have to start completion: use std::sync::Arc;

use datafusion::arrow::datatypes::DataType;
use datafusion::logical_expr::{create_udaf, AggregateUDF, Volatility};
use datafusion::physical_plan::expressions::AvgAccumulator;
use spi::query::function::FunctionMetadataManager;
use spi::Result;

pub fn register_udaf(func_manager: &mut dyn FunctionMeta
    
fn new() -> AggregateUDF {
    create_udaf(
        "MY_AVG",
        DataType::Float64,
        Arc::new(DataType::Float64),
        Volatility::Immutable,
        Arc::new(|_, _| {
            Ok(Box::new(AvgAccumulator::try_new(
                &DataType::Float64,
                &DataType::Float64,
            )?))
        }),
        Arc::new(vec![DataType::UInt64, DataType::Float64]),
    )
}