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Managing this variable correctly can be tedious, so MaxwellMayaAPI so MaxwellMayaAPI provides a few static inline methods for it: SetExportCallback(), RemoveExportCallback() and RemoveExportCallbacks(). These can be called without loading the API. If you do not need these methods and do not want them declared, you can define the MAXWELL_MAYA_NO_CALLBACK_HELPERS macro before including MaxwellMayaAPI.h.
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