def call_function(tb_stack):
    """ Return the function that uses the annotation """
    i = 0
    call_func = []
    temp_tb = []
    while i != len(tb_stack):
        temp_tb = tb_stack[i].splitlines()
        if 'ann[name][0](val, *ann[name][1:])' in temp_tb[1
            ] or 'ann[name](val)' in temp_tb[1]:
            call_func = tb_stack[i - 1]
            break
        i = i + 1
    return call_func.splitlines()[1]
