def set_global_constants(include_damping_in_qmodel_change=None):
    """Sets various global constants used by the classes in this module."""
    global _INCLUDE_DAMPING_IN_QMODEL_CHANGE
    if include_damping_in_qmodel_change is not None:
        _INCLUDE_DAMPING_IN_QMODEL_CHANGE = include_damping_in_qmodel_change
