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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 change_exteditor(self):

 """Change external editor path"""

        path, valid = QInputDialog.getText(self, _('External editor'),
                          _('External editor executable path:'),
                          QLineEdit.Normal,
                          self.get_option('external_editor/path'))
        if valid:
            self.set_option('external_editor/path', to_text_string(path))