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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_open_input_tool_clicked(self):
 """Autoconnect slot activated when open input tool button is clicked. """

        input_path = self.input_path.text()
        if not input_path:
            input_path = os.path.expanduser('~')
        # noinspection PyCallByClass,PyTypeChecker
        filename, __ = QFileDialog.getOpenFileName(
            self, tr('Input file'), input_path, tr('Raw grid file (*.xml)'))
        if filename:
            self.input_path.setText(filename)