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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 add_project(self, ):
 """Add a project and store it in the self.projects :returns: None :rtype: None :raises: None """

        i = self.prj_tablev.currentIndex()
        item = i.internalPointer()
        if item:
            project = item.internal_data()
            if self._atype:
                self._atype.projects.add(project)
            elif self._dep:
                self._dep.projects.add(project)
            else:
                project.users.add(self._user)
            self.projects.append(project)
            item.set_parent(None)