import pandas as pd
from typing import Any, cast, Union, Dict

def max_at( data: pd.DataFrame, col: str ) -> Any:
    return data[data[col] == data[col].max()]

def best( data: pd.DataFrame ) -> pd.DataFrame:
    d = max_at( data, 'weekly' )
    e = max_at( data, 'assignments' )
    f = max_at( data, 'reviews' )
    return cast( pd.DataFrame, d.combine_first( e ).combine_first( f ) )

def get_total( data: pd.DataFrame ) -> pd.Series:
    x = data['weekly'].apply( lambda x: min( x, 9 ) ) + data['assignments'] + data['reviews']
    assert isinstance( x, pd.Series )
    return x

def add_total( data: pd.DataFrame ) -> pd.DataFrame:
    return data.assign( total = get_total )

def compute_total( data: pd.DataFrame ) -> pd.DataFrame:
    tot = add_total( data )
    return tot[ [ 'student', 'total' ] ]

def compute_averages( data: pd.DataFrame ) -> Dict[ str, float ]:
    return dict( add_total( data ).mean() )