Will dequeue from the input queue if necessary (e.g. when the
Reader needs to start reading from a new file since it has finished
with the previous file).
It may return less than num_records even before the last batch.
Args
reader_handle
A Tensor of type resource. Handle to a Reader.
queue_handle
A Tensor of type resource.
Handle to a Queue, with string work items.
num_records
A Tensor of type int64.
number of records to read from Reader.