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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 pythonpath_changed(self):

 """Projects PYTHONPATH contribution has changed"""

        self.remove_path_from_sys_path()
        self.project_path = self.projects.get_pythonpath()
        self.add_path_to_sys_path()
        self.sig_pythonpath_changed.emit()