parameters: (self, key, value)
docstring: Add the key and value, not overwriting any previous value.
docstring_summary: Add the key and value, not overwriting any previous value.
docstring_tokens: Add the key and value not overwriting any previous value .
function: def add(self, key, value):
          """
          Add the key and value, not overwriting any previous value.
          """
          self._items.append((key, value))
function_tokens: def add ( self , key , value ) : self . _items . append ( ( key , value ) )