def METHOD_NAME(self):
    """Returns grand total number of ngrams stored.
    This includes ngrams from all orders, so some duplication is expected.
    :rtype: int
    >>> from nltk.lm import NgramCounter
    >>> counts = NgramCounter([[("a", "b"), ("c",), ("d", "e")]])
    >>> counts.N()
    3
    """
    return sum(val.METHOD_NAME() for val in self._counts.values())