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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def create_prj_model(self, ):
 """Create and return a tree model that represents a list of projects :returns: the creeated model :rtype: :class:`jukeboxcore.gui.treemodel.TreeModel` :raises: None """

        prjs = djadapter.projects.all()
        rootdata = treemodel.ListItemData(['Name', 'Short', 'Rootpath'])
        prjroot = treemodel.TreeItem(rootdata)
        for prj in prjs:
            prjdata = djitemdata.ProjectItemData(prj)
            treemodel.TreeItem(prjdata, prjroot)
        prjmodel = treemodel.TreeModel(prjroot)
        return prjmodel