Sub-SBML is a Python based toolbox to create, edit, combine, and model interactions among multiple Systems Biology Markup Language (SBML) models. Sub-SBML works with a “subsystem” architecture of modeling where a single SBML model can be contained within a subsystem. Three major functionalities are developed in Sub-SBML that take advantage of this subsystem framework of modeling –
creating subsystems, combining multiple subsystems, and modeling interactions such as transport of molecules and input-output relationships among multiple subsystems.

Refer to the Wiki for more information.

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