def sanity_check():
    """
    Perform an initial sanity check before doing anything else in a given workflow.
    This function can be used to verify importing of modules that are otherwise used much later, but it is better to abort
    the pilot if a problem is discovered early.

    :return: exit code (0 if all is ok, otherwise non-zero exit code).
    """
    exit_code = 0
    return exit_code
