(self)
Returns True if this index is empty (that is, it has never had any
        documents successfully written to it.
Returns True if this index is empty (that is, it has never had any
        documents successfully written to it.
Returns True if this index is empty ( that is it has never had any documents successfully written to it .
def is_empty(self):
        """Returns True if this index is empty (that is, it has never had any
        documents successfully written to it.
        """
        raise NotImplementedError
def is_empty ( self ) : raise NotImplementedError