from typing import Dict


def parse_guid(guid: str) -> Dict[str, int]:
    """
    Parse a guid back to its four constituents

    Args:
        guid: a valid guid str

    Returns:
        A dict with keys 'location', 'work_station', 'sample', and 'time'
          as integer values
    """
    guid = guid.replace('-', '')
    components = {}
    components['sample'] = int(guid[:8], base=16)
    components['location'] = int(guid[8:10], base=16)
    components['work_station'] = int(guid[10:16], base=16)
    components['time'] = int(guid[16:], base=16)

    return components