code: def site_param(dic):
      
      new = {}
      for name, val in dic.items():
          if name == 'vs30Type':
              # avoid "Unrecognized parameter vs30Type"
              new['vs30measured'] = val == 'measured'
          elif name not in site.site_param_dt:
              raise ValueError('Unrecognized parameter %s' % name)
          else:
              new[name] = val
      return new
docs: Convert a dictionary site_model_param -> string into a dictionary
      of valid casted site parameters.