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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 set_project_path(self, path):

 """
 Sets the project path and disables the project search in the combobox
 if the value of path is None.
 """

        if path is None:
            self.project_path = None
            self.model().item(PROJECT, 0).setEnabled(False)
            if self.currentIndex() == PROJECT:
                self.setCurrentIndex(CWD)
        else:
            path = osp.abspath(path)
            self.project_path = path
            self.model().item(PROJECT, 0).setEnabled(True)