from typing import IO
from io import StringIO


def input_stream() -> IO:
    """Input stream fixture."""
    return StringIO(
        """class: 1-3 or 5-7
row: 6-11 or 33-44
seat: 13-40 or 45-50

your ticket:
7,1,14

nearby tickets:
7,3,47
40,4,50
55,2,20
38,6,12"""
    )