docs: def add_value(self, value, metadata=""):
          """
          Add a canned value
  
          :type value: str
          :param value: New canned value
  
          :type metadata: str
          :param metadata: Optional metadata
  
          :rtype: dict
          :return: A dictionnary containing canned value description
          """
          data = {
              'value': value,
              'metadata': metadata
          }
  
          return self.post('createValue', data)