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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 dep_add_prj(self, *args, **kwargs):
 """Add projects to the current department :returns: None :rtype: None :raises: None """

        if not self.cur_dep:
            return

        dialog = ProjectAdderDialog(department=self.cur_dep)
        dialog.exec_()
        prjs = dialog.projects
        for prj in prjs:
            prjdata = djitemdata.ProjectItemData(prj)
            treemodel.TreeItem(prjdata, self.dep_prj_model.root)