'Get next data batch from iterator.
Returns
DataBatch
The data of next batch.
Raises
StopIteration
If the end of the data is reached.'

def next(self):

    if self.iter_next():
        return DataBatch(data=self.getdata(), label=self.getlabel(), pad=self.getpad(), index=self.getindex())
    else:
        raise StopIteration
