text: 
  class damagefunctions:
      def pistrika_US_2010_block_group(water_depth_m, velocity_ms):
          """Damage fraction [0-1] from water depth (m) and flow velocity (m/s) using Pistrika and Jonkman (2010) results for block group
          Parameters
          ----------
          water_depth_m : float, (default : None)
              Water depth in meters
          velocity_ms : float, (default : None)
              Flow velocity in m/s
          Returns
          -------
          Damage ratio between 0 and 1.
          References
          ----------
          * (Pristrika and Jonkman (2010))[https://link.springer.com/article/10.1007/s11069-009-9476-y]
          """
          return 0.422+0.075*water_depth_m*velocity_ms**0.682
  
      def pistrika_US_2010_block(water_depth_m, velocity_ms):
          """Damage fraction [0-1] from water depth (m) and flow velocity (m/s) using Pistrika and Jonkman (2010) results for block
          Parameters
          ----------
          water_depth_m : float, (default : None)
              Water depth in meters
          velocity_ms : float, (default : None)
              Flow velocity in m/s
          Returns
          -------
          Damage ratio between 0 and 1.
          References
          ----------
          * (Pristrika and Jonkman (2010))[https://link.springer.com/article/10.1007/s11069-009-9476-y]
          """
          return 0.457+0.063*water_depth_m*velocity_ms**0.654