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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_output_path_textChanged(self):
 """Action when output file name is changed."""

        output_path = self.output_path.text()
        output_not_xml_msg = tr('output file is not .tif')
        if output_path and not output_path.endswith('.tif'):
            self.warning_text.add(output_not_xml_msg)
        elif output_path and output_not_xml_msg in self.warning_text:
            self.warning_text.remove(output_not_xml_msg)
        self.update_warning()