code: def to_nullable_map(value):
          
          if value == None:
              return None
  
          # Parse JSON
          try:
              value = json.loads(value)
              return RecursiveMapConverter.to_nullable_map(value)
          except:
              return None
docs: Converts JSON string into map object or returns null when conversion is not possible.
  
          :param value: the JSON string to convert.
  
          :return: Map object value or null when conversion is not supported.