[TYPO3-mvc] How To find Repository Class by Object? Function available?

[Steffen Ritter]

Hey list,
im currently working on a tool set.
Want to create Template-Class.

like MyClass<Tx_myModel>
inside this class I need to instanciate an repository matching the Model.

Is there any Function which might help, converting the ClassName to the 
Repository Class or should I hack the string myself?