def default(copysets, copyset):
    """Check that always passes.

    The check function checks for custom constraints, such as rack or
    tier awareness. 'copysets' contains a list of copysets
    build_copysets has generated so far, and 'copyset' is the copyset
    that build_copysets wants to check as a valid.

    This is the default check, meaning we don't care about constraints
    such as rack awareness.

    """

    return True