code: def _check_seismogenic_depths(self, upper_depth, lower_depth):
          '''
          Checks the seismic depths for physical consistency
          :param float upper_depth:
              Upper seismogenic depth (km)
          :param float lower_depth:
              Lower seismogenis depth (km)
          '''
          # Simple check on depths
          if upper_depth:
              if upper_depth < 0.:
                  raise ValueError('Upper seismogenic depth must be greater than'
                                   ' or equal to 0.0!')
              else:
                  self.upper_depth = upper_depth
          else:
              self.upper_depth = 0.0
  
          if lower_depth:
              if lower_depth < self.upper_depth:
                  raise ValueError('Lower seismogenic depth must take a greater'
                                   ' value than upper seismogenic depth')
              else:
                  self.lower_depth = lower_depth
          else:
              self.lower_depth = np.inf _check_seismogenic_depths(self, upper_depth, lower_depth):
          '''
          Checks the seismic depths for physical consistency
          :param float upper_depth:
              Upper seismogenic depth (km)
          :param float lower_depth:
              Lower seismogenis depth (km)
          '''
          # Simple check on depths
          if upper_depth:
              if upper_depth < 0.:
                  raise ValueError('Upper seismogenic depth must be greater than'
                                   ' or equal to 0.0!')
              else:
                  self.upper_depth = upper_depth
          else:
              self.upper_depth = 0.0
  
          if lower_depth:
              if lower_depth < self.upper_depth:
                  raise ValueError('Lower seismogenic depth must take a greater'
                                   ' value than upper seismogenic depth')
              else:
                  self.lower_depth = lower_depth
          else:
              self.lower_depth = np.inf
docs: Checks the seismic depths for physical consistency
          :param float upper_depth:
              Upper seismogenic depth (km)
          :param float lower_depth:
              Lower seismogenis depth (km)