(self)
return len(self._variables) + len(self._metas)
The number of variables (features and class attributes).

        The current behavior returns the length of only features and
        class attributes. In the near future, it will include the
        length of metas, too, and __iter__ will act accordingly.
The number of variables (features and class attributes).
The number of variables ( features and class attributes ) .
def __len__(self):
        """The number of variables (features and class attributes).

        The current behavior returns the length of only features and
        class attributes. In the near future, it will include the
        length of metas, too, and __iter__ will act accordingly."""
        return len(self._variables) + len(self._metas)
def __len__ ( self ) : return len ( self . _variables ) + len ( self . _metas )