def get_block_name(path, seq):
    """Return block id (name) for given file path and seq."""
    # Replace / with - and append seq number
    # No validation done on path or block
    # Chances of colision. E.g: /a/b/c and /a/b-c both map to a-b-c
    # Also first character is always a - (because path starts with /). Meh.
    return "{}-{}".format(path.replace("/", "-"), str(seq))