@classmethod
def fromData(cls, type, data, startOffset=0):
    """
        Create an instance of the SequenceEvent subclass this function
        is called on, using a particular type value and reading data
        beginning at some offset. This abstract base class
        implementation simply raises NotImplementedError.
        """
    raise NotImplementedError(
        'SequenceEvent subclasses that can load themselves from data without context can implement this.'
        )
