Deletes records associated with a particular hash

    :param str hash: The hash

    :rtype int: The number of records deleted

def delete_io( hash ):
    """
    Deletes records associated with a particular hash

    :param str hash: The hash

    :rtype int: The number of records deleted
    """
    global CACHE_
    load_cache(True)
    record_used('cache', hash)
    num_deleted = len(CACHE_['cache'].get(hash, []))
    if hash in CACHE_['cache']:
        del CACHE_['cache'][hash]
    write_out()
    return num_deleted