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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 on_input_path_textChanged(self):
 """Action when input file name is changed."""

        input_path = self.input_path.text()
        input_not_grid_msg = tr('input file is not .xml')

        if input_path and not input_path.endswith('.xml'):
            self.warning_text.add(input_not_grid_msg)
        elif input_path and input_not_grid_msg in self.warning_text:
            self.warning_text.remove(input_not_grid_msg)

        if self.use_output_default.isChecked():
            self.get_output_from_input()
        self.update_warning()