docs: def getbool(self, key, **kwargs):
          """
          Gets the setting value as a :func:`bool` by cleverly recognizing true values.
  
          :rtype: bool
          """
  
          def _string_to_bool(s):
              if isinstance(s, str):
                  if s.strip().lower() in ('true', 't', '1'): return True
                  elif s.strip().lower() in ('false', 'f', '0', 'None', 'null', ''): return False
  
                  raise ValueError('Unable to get boolean value of "{}".'.format(s))
              #end if
  
              return bool(s)
          #end def
  
          return self.get(key, cast_func=_string_to_bool, **kwargs)