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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 selected_impact_function_constraints(self):
 """Obtain impact function constraints selected by user. :returns: Tuple of metadata of hazard, exposure, hazard layer geometry and exposure layer geometry :rtype: tuple """


        hazard = self.step_fc_functions1.selected_value(
            layer_purpose_hazard['key'])
        exposure = self.step_fc_functions1.selected_value(
            layer_purpose_exposure['key'])

        hazard_geometry = self.step_fc_functions2.selected_value(
            layer_purpose_hazard['key'])
        exposure_geometry = self.step_fc_functions2.selected_value(
            layer_purpose_exposure['key'])
        return hazard, exposure, hazard_geometry, exposure_geometry